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Urinary Schistosomiasis is neglected tropical disease (NTDs) caused by the trematode, Schistosoma haematobium. This Study was designed to comparatively observe the use of Combi 10 and filter paper in the diagnosis of Schistosoma hameatobium, and to determine the prevalence and intensity of the Infection among Primary School Pupils in Makurdi Metropolis. A survey involving 202 pupils from four different primary schools within the Makurdi Metropolis was conducted. Urine samples were collected from pupils between the ages 5 to 19 and examined for hematuria and Ova of Schistosoma haematobium using Medi Test Combi 10 and Polycarbonate Filters in Urine Syringe Filtration Technique (USFT) respectively. The prevalence of Schistosoma haematobium based on microscopic examination of Filter papers was 25.7% while prevalence of Hematuria was 35%. Prevalence of Proteinuria was observed to be 50% Infection Intensity varied from Light to heavy. In general infection was higher among males (26.3%) than females (25.8%; P>0.05) although statistically non-significant. The age specific prevalence ranged from 11.1% to 40% in 5-9 years and 15-19 years respectively (P >0.05), and showed no significant difference. There was also a strong positive correlation between the use Medi-test Combi 10 reagent strips and Poly membrane Filtration technique. A total of 111 urine samples were positive to haematuria using combi 10 while only 52 urine samples were positive to S. haematobium using poly membrane filter paper, hence correlation is significant at 0.05 level. The above finding shows that S. haematobiumis prevalent among primary school pupils and the use of Combi 10 and Filter paper are both diagnostic tools that can be used in S. haematobium diagnosis. They can both ascertain the prevalence of the disease will provide a guide for the treatment and eradicating of the infection. Hence, decisive control measures including administration of praziquantel to pupils are needed.

The aim of the study was to validate the Portuguese language version of the 10-item Cervantes Scale (CS-10), a self-reporting instrument that assesses menopausal symptoms, and to compare the results (both symptom severity and multigroup invariance) of middle-aged women who completed the questionnaire in paper-and-pencil format (PPF) or in the online format (OF).A total of 292 women, aged 45 to 65 years, completed the questionnaires (PPF = 66; OF = 226). Construct (factorial and convergent) and external validity, as well as reliability and psychometric sensitivity were studied. Multigroup confirmatory factor analysis was performed to compare PPF with OF, regarding the measure's invariance.The CS-10 showed good psychometric properties (ie, factor and external validity), as well as good sensitivity and reliability. The association with the Utian Quality of Life Scale (UQoLS) was significant and positive, though weak. The measured structure was invariant when comparing both subsamples (PPF and OF), evidencing an equivalent structure in both. No differences in reported symptoms were observed between the two subgroups.The Portuguese language version of the CS-10 rendered data with good psychometric properties in a sample of middle-aged Portuguese women. Therefore, it can be used in both clinical and community settings. The weak association between both instruments (UQoLS and CS-10) might be due to the different conceptualization of the quality of life construct: the CS-10 focuses on symptom severity, whereas the UQoLS assesses domains such as work-related or health-related behaviors.

Many complex physical systems exhibit a rich variety of discrete behavioural modes. Often, the system complexity limits the applicability of standard modelling tools. Hence, understanding the underlying physics of different behaviours and distinguishing between them is challenging. Although traditional machine learning techniques could predict and classify behaviour well, typically they do not provide any meaningful insight into the underlying physics of the system. In this paper we present a novel method for extracting physically meaningful clusters of discrete behaviour from limited experimental observations. This method obtains a set of physically plausible functions that both facilitate behavioural clustering and aid in system understanding. We demonstrate the approach on the V-shaped falling paper system, a new falling paper type system that exhibits four distinct behavioural modes depending on a few morphological parameters. Using just 49 experimental observations, the method discovered a set of candidate functions that distinguish behaviours with an error of 2.04%, while also aiding insight into the physical phenomena driving each behaviour. © 2019 Howison et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

The bending response analysis of a piece paper as a result of its interaction with water is studied to provide a better understanding of the problem that is dominated by water imbibition into paper. Three phenomenon that take simultaneously place are considered in this model: (i) water imbibition (ii) swelling of fibers and (iii) the softening effect on paper due to the water penetration. The water penetration into paper is modeled including the nonlinear imbibition phenomenon into paper. Numerical solution of the problem is carried out using MatLab ® . The influence of the nonlinear imbibition on the bending response is studied. The proposed model is more accurate and provides a better understanding of the problem compared to previous models presented in earlier works. Moreover, the formulation requires only four parameters to characterize the hygro-mechanical bending response of paper. Finally, the results show a good agreement with the experimental measurements reported in the literature.

I commend Drs. Prentice and Huang (PH) for their continued and longstanding commitment to the generation of knowledge concerning the nutritional causes of chronic diseases, and in their dedication ...

SUMMARY Digital books have become popular as electronic media has become more common. An evaluation that includes not only a subjective assessment of readability or usability, but also an objective assessment of psychometric health impact is needed. The goal of this study is an objective assessment of the physiological and psychological effects of reading books using electronic or paper media. This paper focuses on hemodynamic parameters. The measurement items include VAS and POMS as a psychological index and hemodynamic parameters as a physiological index. As a result, low levels of vigor and limited readability were recognized as significant (p < 0.05) when reading a book using electronic media as compared to paper media. The cardiovascular system was actively engaged in coping because of sympathetic hyperactivity in the hemodynamic reaction. By contrast, using electronic media was not seen to involve stress coping. We also found that the parasympathetic nervous system activity was enhanced by the illegibility of sentences and fatigue due to using electronic media. Based on all of these results, we identified a difference in how people react physiologically when reading a book using electronic and paper media.

Stiffness based sorting of mixed paper waste at high speed is desirable for sorting board, cardstock, and paper from each other for efficient recycling. We propose a quick, non-contact method for measuring the relative stiffness of paper samples moving on a conveyor at high speeds. The method consists of impinging an air jet on a moving paper sample while it is crossing a gap during transfer from one conveyor belt to another. The deflection caused by the impinging air jet can be measured and used to categorize different grades of paper. In this paper, we report results from a simulation of the proposed method using a finite element model. Influence of conveyor speed, sample orientation and nozzle pressure is studied using the model. Results indicate that the stiffness estimation has sufficient resolution to distinguish between board and paper grades at high conveyor speeds.

Objective WeChat is a promising tool for capturing electronic data; however, no research has examined its use. This study evaluates the reliability and feasibility of WeChat for administering the Pelvic Floor Impact Questionnaire Short Form 7 questionnaire to women with pelvic floor disorders. Methods Sixty-eight pelvic floor rehabilitation women were recruited between June and December 2015 and crossover randomized to two groups. All participants completed two questionnaire formats. One group completed the paper version followed by the WeChat version; the other group completed the questionnaires in reverse order. Two weeks later, each group completed the two versions in reverse order. The WeChat version's reliability was assessed using intraclass correlation coefficients and test-retest reliability. Results Forty-two women (61.8%) preferred the WeChat to the paper format, eight (11.8%) preferred the paper format, and 18 (26.5%) had no preference. The younger women preferred WeChat. Completion time was 116.5 (61.3) seconds for the WeChat version and 133.4 (107.0) seconds for the paper version, with no significant difference (P = 0.145). Age and education did not impact completion time (P > 0.05). Consistency between the WeChat and paper versions was excellent. The intraclass correlation coefficients of the Pelvic Floor Impact Questionnaire Short Form 7 and the three subscales ranged from 0.915 to 0.980. The Bland-Altman analysis and linear regression results also showed high consistency. The test-retest study had a Pearson's correlation coefficient of 0.908, demonstrating a strong correlation. Conclusions WeChat-based questionnaires were well accepted by women with pelvic floor disorders and had good data quality and reliability.

Utilization of ferric chelates for the oxidation of hydrogen sulfide is beneficial from the standpoint of iron-sequestration and protection against precipitation in the alkaline environments characteristic of the Kraft mill effluents. Availability of oxygen along with hydrogen sulfide in the atmospheric emissions of pulp and paper industries is beneficial for the simultaneous Redox regeneration from ferrous to ferric chelates. By putting together these two premises, the concept of a multifunctional Redox process for the scrubbing of hydrogen-sulfide-contaminated atmospheric effluents emanating from the Kraft mills is formulated, modeled and simulated. This paper discusses from a multiphase reactor engineering perspective, the design of a countercurrent packed-bed bifunctional scrubber by setting an exhaustive modeling framework in which are solved both the oxidation of hydrogen sulfide in reactive ferric chelate solutions of ethylenediaminetetraacetic acid (EDTA chelate) and the simultaneous oxidative regeneration of ferrous chelates resulting from oxidation of hydrogen sulfide. A one-dimensional model based on the transient species balance equations in the gas and liquid phases coupled with the transient film model according to the film-penetration theory was developed for the description of the time and space evolution of the species concentrations along the scrubber. The oxidative regeneration of the ferrous chelate showed a synergistic effect resulting in increased enhancement factor for the hydrogen sulfide oxidation. Availability of plenty of oxygen in the atmospheric effluent precluded starvation of the ferric form and maintained high reaction rates of hydrogen sulphide removal along the whole reactor length.

Ensuring the growth of effective science education across the African continent is of significant importance to addressing global issues in health, agriculture, economic development and environmental sustainability. There is now a significant number of researchers in science education for African contexts as universities proliferate across Africa and African postgraduate students study across the globe. While the challenges facing science education in Africa are many, an important strategy for supporting quality enhancement in teacher development and curriculum development is the provision of sound research into what works in the resource-restricted educational environments of Africa. The ten papers in this Special Issue address a wide range of range of topics in Mathematics, Science and Technology Education (MSTE) in Africa. Several papers focus on teacher development so that teaching strategies can engage students in meaningful learning. As these studies show, learning activities for students of all ages need to be designed so that they immerse students in interactive, authentic scenarios. There can be no shortcuts. It is time that MSTE world-wide focused on this principle. Let me be quite clear: There is ample research evidence that a factory model of education is inefficient and minimally effective. If we want to use precious resources wisely, educational policy needs to focus on teacher development and curriculum development to produce learning environments where students are enthused by learning and can achieve the knowledge, skills and attitudes that will enable them to contribute to the myriad of problems facing countries in Africa and the entire globe. This requires a genuinely transformational approach to conceptualizing education systems, physical designs for schools, initial teacher education and ongoing teacher development. The world cannot afford to waste resources by perpetuating existing outmoded models for schooling and teacher education. I am grateful to colleagues world-wide who acted as peer reviewers for the Special Issue. This form of collegial service is often insufficiently recognized and yet it is the backbone of a global academic community. I am also deeply appreciative of the work of the editorial team of the EURASIA Journal of Mathematics, Science and Technology Education who have worked with the authors and myself to produce this Special Issue. Finally, my heartfelt thanks to all the authors whose dedication to the refinement of their research has been done willingly and with diligence. This collection is presented in the firm belief that it will be a useful resource for teachers, teacher educators and policy makers, as well as supporting further research on MSTE in Africa and elsewhere.

Objective. To objectively evaluate the quality and effectiveness of teaching and identify the problems in the teaching process, and to carry out the comprehensive analysis and evaluation of the final examination paper of medical record informatics. Method. The final examination paper of medical record informatics is analyzed through the education survey. Result. The average score of the examination paper is 70.6, and the examination results obey normal distribution. The examination paper has the features of moderate difficulty, general discrimination and good reliability. The proportion of easy questions is too large, and the proportion of the relatively difficult questions should be increased. Conclusion. The proportion of the relatively difficult questions on the examination paper should be increased promptly, so that the examination paper with moderate difficulty can objectively reflect the actual level of the students, thereby improving the quality of teaching.

Many in situ x-ray tomography studies require experimental rigs which may partially occlude the beam and cause parts of the projection data to be missing. In a study of fluid flow in porous chalk using a percolation cell with four metal bars drastic streak artifacts arise in the filtered backprojection (FBP) reconstruction at certain orientations. Projections with non-trivial variable truncation caused by the metal bars are the source of these variable-truncation artifacts. To understand the artifacts a mathematical model of variable-truncation data as a function of metal bar radius and distance to sample is derived and verified numerically and with experimental data. The model accurately describes the arising variable-truncation artifacts across simulated variations of the experimental setup. Three variable-truncation artifact-reduction methods are proposed, all aimed at addressing sinogram discontinuities that are shown to be the source of the streaks. The ‘reduction to limited angle’ (RLA) method simply keeps only non-truncated projections; the ‘detector-directed smoothing’ (DDS) method smooths the discontinuities; while the ‘reflexive boundary condition’ (RBC) method enforces a zero derivative at the discontinuities. Experimental results using both simulated and real data show that the proposed methods effectively reduce variable-truncation artifacts. The RBC method is found to provide the best artifact reduction and preservation of image features using both visual and quantitative assessment. The analysis and artifact-reduction methods are designed in context of FBP reconstruction motivated by computational efficiency practical for large, real synchrotron data. While a specific variable-truncation case is considered, the proposed methods can be applied to general data cut-offs arising in different in situ x-ray tomography experiments.

The importance of paper-based medical records is gradually becoming neglected under the double-track mode of electronic medical records coexisting with paper medical records. There are many problems in the management of paper medical records, such as delayed printing and signing of medical records, missing inspection and laboratory test reports, and delayed medical record recovery. We shall ensure medical record safety and reduce medical risk by improving the attention and awareness of leadership and medical workers at all levels, strengthening the monitoring of medical records, and linking medical record management to the performance evaluation.

This study proposes a new method for the characterization of paper surface and bulk structure: optical coherence tomography (OCT). Although having been used in medicine for years, this technique is still relatively unknown in the paper-making industry. First, we provide a brief description of a conventional PC-controlled measurement system for the OCT imaging of paper. In this set-up, a powerful superluminescent diode is used to illuminate a Michelson interferometer with a free-space configuration, and a piezo-transducer is placed in the optical delay line to modulate the measurement signal for optical heterodyne detection. The set-up is then applied to demonstrate the ability of the technique to visualize the surface structures of widely disparate paper samples using a single device. Next, the paper provides 3D images of a fibre network and of typical copy paper. The results prove that OCT is applicable not only to the 3D imaging of simple wood fibre networks, but also to the imaging of complex commercial paper, provided that an appropriate clearing agent is used. Finally, the effect of filler on the OCT signal slope calculated by averaging several A-scans from the sample is demonstrated, showing that increasing filler content produces a corresponding decrease of decay of the A-scan in depth.

Objectives. To analyze the ratio of utilization of medical records used in writing medical papers for the medical staff. Methods. Papers published in the Chinese Medical Series Journals and the Core Journals are subjected to statistical analysis by using the method of proportion in the statistical description, so as to analyze the utilization of clinical articles, case reports and so on. Results. The clinical articles written utilizing medical records accounted for 35.45% in the Chinese Medical Series Journals and 55.00% in the Core Journals. The figure is a little low for a comprehensive tertiary hospital. Conclusions. Increasing the utilization of medical records is a prerequisite in papers, as it enhances their number and quality in a stable manner. It is an important problem which needs attention and study.

The current study compared student performance between paper-and-pencil testing (PPT) and computer-based testing (CBT) on a large-scale statewide end-of-course English examination. Analyses were conducted at both the item and test levels. The overall results suggest that scores obtained from PPT and CBT were comparable. However, at the content domain level, a rather large difference in the reading comprehension section suggests that reading comprehension test may be more affected by the test administration mode. Results from the confirmatory factor analysis suggest that the administration mode did not alter the construct of the test.

A reduction in population salt intake is one of the most cost-effective measures to prevent cardiovascular disease [1, 2]. Two recent articles by O’Donnell et al. in the New England Journal of Medicine attempt to cast doubt on this important public health policy by claiming that a salt intake below 7.5 g/day was not associated with lower blood pressure and related to a higher cardiovascular events or total mortality based on the Prospective Urban Rural Epidemiology study [3, 4]. However, this claim is invalid because of methodological problems as well as errors in using a mathematical formula to estimate daily salt intake from spot urinary sodium.

A paper published by Harry H. Pennes in Volume 1 of the Journal of Applied Physiology defined the theoretical basis for a considerable body of analysis performed by many investigators during the ensuing half century. However, during the past decade, the Pennes’ model of heat transfer in perfused tissue has been criticized for various reasons, one of which is that his own experimental data seemed to be at variance with the model. More specifically, the shape of the mean temperature-depth relationship measured by Pennes was distinctly different from the shape of the theoretical curve. In this paper, I show that Pennes used an inappropriate procedure to analyze his data and that, when the data are analyzed in a more rigorous manner, they support his theory. Additional support for Pennes’ theory is provided by the experimental data of H. Barcroft and O. G. Edholm [ J. Physiol. (Lond.) 102: 5–20, 1942 and 104: 366–376, 1946], who had previously studied cooling of the forearm during immersion in water at various temperatures.

The paper by Rao and Kakehashi [1] uses the Weibull distribution (given by equation (3) in the paper) and a truncated version of it (given by equations (4) and (5)) to model HIV/AIDS data in India. After a careful reading, I have found that all of the results presented in the appendix are incorrect (starting with equation (11) itself). Instead of pointing out all of the specific errors, I have chosen to give the correct formulas (and a brief outline of their derivation) for the $r$th moment of the truncated Weibull distribution.

A SIRS epidemiological model with two subpopulations and vital dynamics is analyzed. Both subpopulations sizes are considered constant by assuming that the birth and the death rates are equal. We consider the case where one subpopulation is a core, that is a very infectious small group, responsible for a big fraction of the incidence. For this case thresholds are determined and the main equilibrium points for the four dimensional system are shown to be globally stable by using a known Theorem of Markus on asymptotically autonomous systems. This system models the dynamics of typhoid fever , where the core is the group of food handlers . The results presented in this work are an extension of those presented in [3].

Budrugeac and Segal (Int. J. Chem. Kinet.33, 564, 2001) have generally criticized the integral isoconversional methods for producing a systematic error in the activation energy, whose value varies with the extent of conversion. We stress that this error is practically eliminated in the advanced integral isoconversional methods when using integration over small time segments (Vyazovkin, S. J. Comput Chem.22, 178, 2001) © 2002 Wiley Periodicals, Inc. Int J Chem Kinet 34: 418–420, 2002

The two papers in this issue are of the analytic kind. The first one deals with symbol calculus, and the second one with compressed sensing. In their paper Discrete Symbol Calculus, Laurent Demanet...

Serum protein fractions have been studied intensively in the normal newborn infant. 1-9 However, there is only sparse information on the cerebrospinal fluid protein fractions in this age group. 10-18 The concentration of the low protein content in small amounts of cerebrospinal fluid has presented a major problem. Earlier studies primarily used precipitation methods which could not separate the individual fractions. The use of dialysis methods for concentrating proteins, combined with paper electrophoresis, now affords adequate means for separation of the various components of cerebrospinal fluid proteins. Paper electrophoretic studies of cerebrospinal fluid have been performed for the most part only in adults and older children, 19-22 with few reports in normal newborn infants. 17,18 The purpose of this study was to determine the distribution and relationship of proteins in the cerebrospinal fluid and serum of normal newborn infants utilizing chemical and paper electrophoretic methods. Method Thirty-five normal newborn infants

Nowadays, humanity is facing one of the most dangerous pandemics known as COVID-19. Due to its high inter-person contagiousness, COVID-19 is rapidly spreading across the world. Positive patients are often suffering from different symptoms that can vary from mild to severe including cough, fever, sore throat, and body aches. In more dire cases, infected patients can experience severe symptoms that can cause breathing difficulties which lead to stern organ failure and die. The medical corps all over the world are overloaded because of the exponentially myriad number of contagions. Therefore, screening for the disease becomes overwrought with the limited tools of test. Additionally, test results may take a long time to acquire, leaving behind a higher potential for the prevalence of the virus among other individuals by the patients. To reduce the chances of infection, we suggest a prediction model that distinguishes the infected COVID-19 cases based on clinical symptoms and features. This model can be helpful for citizens to catch their infection without the need for visiting the hospital. Also, it helps the medical staff in triaging patients in case of a deficiency of medical amenities. In this paper, we use the non-dominated sorting genetic algorithm (NSGA-II) to select the interesting features by finding the best trade-offs between two conflicting objectives: minimizing the number of features and maximizing the weights of selected features. Then, a classification phase is conducted using an AdaBoost classifier. The proposed model is evaluated using two different datasets. To maximize results, we performed a natural selection of hyper-parameters of the classifier using the genetic algorithm. The obtained results prove the efficiency of NSGA-II as a feature selection algorithm combined with AdaBoost classifier. It exhibits higher classification results that outperformed the existing methods.

The necessity of developing certified reference materials (CRM) for the composition of mineral oil with a certified value of the mass fraction of water, traceable to the State Primary Standard of units of mass fraction and mass (molar) concentration of water in solid and liquid substances and materials GET 173–2017 is revealed proceeding from the review of standardized methods for determining the quality of mineral oils and approved types of reference materials (CRMs). Mineral hydraulic oil MIL-H-5606 of CONOSTAN series manufactured by SCP SCIENCE (Canada) was chosen as the CRM material to control the accuracy of the results of water determination in mineral oils using IR spectrometers. A procedure for reproducing the mass fraction of water in a mineral oil using a standard installation based on coulometric titration according to Karl Fischer method from the composition of GET 173–2017 has been developed. The relative expanded uncertainty (atk= 2) of measurement results of the water mass fraction in mineral oil is 7.1%. The requirements to the metrological characteristics of CRM were formulated: the interval of permissible certified values, the limits of the permissible values of the absolute error atP= 0.95, and the permissible value of the absolute expanded uncertainty atk= 2. The choice of the method of packaging and conditions of CRM storage were analyzed. Taking into account the consistency of the measurement results of the water mass fraction obtained by coulometric titration according to Karl Fischer method and using a Fluid Scan infrared spectrometer manufactured by Spectro Inc., USA, the applicability of CRMs for metrological support of express IR spectrometers was demonstrated.

A novel approach to link the environmental stresses with the COVID-19 cases is adopted during this research. The time-dependent data are extracted from the online repositories that are freely available for knowledge and research. Since the time series data analysis is desired for the COVID-19 time-dependent frequent waves, here in this manuscript, we have developed a time series model with the aid of "nonlinear autoregressive network with exogenous inputs (NARX)" approach. The distribution of infectious agent-containing droplets from an infected person to an uninfected person is a common form of respiratory disease transmission. SARS-CoV-2 has mainly spread via short-range respiratory droplet transmission. Airborne transmission of SARS-CoV-2 seems to have occurred over long distances or times in unusual conditions; SARS-CoV-2 RNA was found in PM10 collected in Italy. This research shows that SARS-CoV-2 particles adsorbed to outdoor PM remained viable for a long time, given the epidemiology of COVID-19, outdoor air pollution is unlikely to be a significant route of transmission. In this research, ANN time series is used to analyze the data resulting from the COVID-19 first and second waves and the forecasted results show that air pollution affects people in different areas of Italy and make more people sick with covid-19. The model is developed based on the disease transmission data of Italy.

One of the main concerns during the COVID-19 pandemic was the protection of healthcare workers against the novel coronavirus. The critical role and vulnerability of healthcare workers during the COVID-19 pandemic leads us to derive a mathematical model to express the spread of coronavirus between the healthcare workers. In the first step, the SECIRH model is introduced, and then the mathematical equations are written. The proposed model includes eight state variables, i.e., Susceptible, Exposed, Carrier, Infected, Hospitalized, ICU admitted, Dead, and finally Recovered. In this model, the vaccination, protective equipment, and recruitment policy are considered as preventive actions. The formal confirmed data provided by the Iranian ministry of health is used to simulate the proposed model. The simulation results revealed that the proposed model has a high degree of consistency with the actual COVID-19 daily statistics. In addition, the roles of vaccination, protective equipment, and recruitment policy for the elimination of coronavirus among the healthcare workers are investigated. The results of this research help the policymakers to adopt the best decisions against the spread of coronavirus among healthcare workers.

This note presents some comments on Bonder's paper on the Lanchester attrition-rate coefficient, which indicate that a valid prediction of average attrition is obtained by using the harmonic mean of the variable attrition rates rather than the arithmetic mean. This change results in a constant Lanchester attrition-rate coefficient being defined as the reciprocal of the expected time to kill a target. An alternate and more general method for obtaining the constant coefficient is presented and some comparative results are displayed. An appendix indicates the conditions for which it is appropriate to use the harmonic and arithmetic means of rates in general.

We analyze the stability of a unique coexistence equilibrium point of a system of ordinary differential equations (ODE system) modelling the dynamics of a metapopulation, more specifically, a set of local populations inhabiting discrete habitat patches that are connected to one another through dispersal or migration. We assume that the inter-patch migrations are detailed balanced and that the patches are identical with intra-patch dynamics governed by a mean-field ODE system with a coexistence equilibrium. By making use of an appropriate Lyapunov function coupled with LaSalle’s invariance principle, we are able to show that the coexistence equilibrium point within each patch is locally asymptotically stable if the inter-patch dispersal network is heterogeneous, whereas it is neutrally stable in the case of a homogeneous network. These results provide a mathematical proof confirming the existing numerical simulations and broaden the range of networks for which they are valid.

Non-invasive estimation of the pressure gradient in cardiovascular stenosis has much clinical importance in assisting the diagnosis and treatment of stenotic diseases. In this research, a systematic comparison is conducted to investigate the accuracy of a group of stenosis models against the MRI- and catheter-measured patient data under the aortic coarctation condition. Eight analytical stenosis models, including six from the literature and two proposed in this study, are investigated to examine their prediction accuracy against the clinical data. The two improved models proposed in this study consider comprehensively the Poiseuille loss, the Bernoulli loss in its exact form, and the entrance effect, of the blood flow. Comparison of the results shows that one of the proposed models demonstrates a cycle-averaged mean prediction error of −0.15 ± 3.03 mmHg, a peak-to-peak prediction error of −1.8 ± 6.89 mmHg, which is the best among the models studied., This research was funded by the European Community’s Seventh Framework Programme (FP7/2007–2013) under the grant agreement number 224495 (euHeart project).

The world is experiencing an ongoing pandemic of coronavirus disease-2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In attempts to control the pandemic, a range of nonpharmaceutical interventions (NPIs) has been implemented worldwide. However, the effect of synchronized NPIs for the control of COVID-19 at temporal and spatial scales has not been well studied. Therefore, a meta-population model that incorporates essential nonlinear processes was constructed to uncover the transmission characteristics of SARS-CoV-2 and then assess the effectiveness of synchronized NPIs on COVID-19 dynamics in China. Regional synchronization of NPIs was observed in China, and it was found that a combination of synchronized NPIs (the travel restrictions, the social distancing and the infection isolation) prevented 93.7% of SARS-CoV-2 infections. The use of synchronized NPIs at the time of the Wuhan lockdown may have prevented as much as 38% of SARS-CoV-2 infections, compared with the unsynchronized scenario. The interconnectivity of the epicenter, the implementation time of synchronized NPIs, and the number of regions considered all affected the performance of synchronized NPIs. The results highlight the importance of using synchronized NPIs in high-risk regions for the control of COVID-19 and shed light on effective strategies for future pandemic responses. Supplementary Information The online version contains supplementary material available at 10.1007/s11071-021-06505-0.

Pandemic is an unprecedented public health situation, especially for human beings with comorbidity. Vaccination and non-pharmaceutical interventions only remain extensive measures carrying a significant socioeconomic impact to defeating pandemic. Here, we formulate a mathematical model with comorbidity to study the transmission dynamics as well as an optimal control-based framework to diminish COVID-19. This encompasses modeling the dynamics of invaded population, parameter estimation of the model, study of qualitative dynamics, and optimal control problem for non-pharmaceutical interventions (NPIs) and vaccination events such that the cost of the combined measure is minimized. The investigation reveals that disease persists with the increase in exposed individuals having comorbidity in society. The extensive computational efforts show that mean fluctuations in the force of infection increase with corresponding entropy. This is a piece of evidence that the outbreak has reached a significant portion of the population. However, optimal control strategies with combined measures provide an assurance of effectively protecting our population from COVID-19 by minimizing social and economic costs.

The utilisation factor for a discrete dam, defined as the stationary probability of non-emptiness of the dam just before release, is obtained for a class of models that includes the Odoom–Lloyd model, the Anis–Lloyd model, the model of Herbert, etc. The method used points to a different approach to measuring dam utilisation via the actual utilisation, which appears to be more fruitful, and this is discussed in the last section.

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The outbreak of the novel coronavirus (COVID-19), which was firstly reported in China, has affected many countries worldwide. To understand and predict the transmission dynamics of this disease, mathematical models can be very effective. It has been shown that the fractional order is related to the memory effects, which seems to be more effective for modeling the epidemic diseases. Motivated by this, in this paper, we propose fractional-order susceptible individuals, asymptomatic infected, symptomatic infected, recovered, and deceased (SEIRD) model for the spread of COVID-19. We consider both classical and fractional-order models and estimate the parameters by using the real data of Italy, reported by the World Health Organization. The results show that the fractional-order model has less root-mean-square error than the classical one. Finally, the prediction ability of both of the integer- and fractional-order models is evaluated by using a test data set. The results show that the fractional model provides a closer forecast to the real data.

Physical degradation assessment of solid insulation in transformers is a challenge to the condition monitoring engineers. Solid insulation degradation in transformer is accessed indirectly by characterizing insulation oil. The present article describes application of dilatometry and X-ray diffraction (XRD) analysis as direct methods to characterize the degradation of transformer solid insulation. Experimental aging on oil/paper insulation has been simulated in laboratory conditions at elevated temperatures. Thermal expansion and shrinkage behavior of cellulose pressboards aged in mineral oil, synthetic ester, and mixed oil have been reported using dilatometry analysis. Measurement of change in cellulose crystal size and relative crystallinity of cellulose kraft papers have been reported using XRD analysis. The detailed procedure and interpretation of the dilatometry and diffractograph signatures for accessing the degradation of solid insulation are explicitly discussed. It is inferred that, dilatometry and XRD analysis provide a direct physical degradation assessment of transformer solid insulation.