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Asymptotical mean-square stability of linear θ-methods for stochastic pantograph diffe...
xiaochen yang
Zhanwen Yang

xiaochen yang

and 2 more

May 23, 2020
The paper deals with the asymptotical mean-square stability of the linear θ-methods under variable stepsize and transformation approach for stochastic pantograph differential equations. A limiting equation for the analysis of numerical stability is introduced by Kronecker products. Under the condition which guarantee the stability of exact solutions, the optimal stability region of the linear θ-methods under variable stepsize is given by using the limiting equation, i.e., θ ∈ (1/ 2,1], which is the same to the deterministic problems. Moreover the linear θ-methods under the transformation approach are also considered and the result of the stability is improved for θ = 1 /2. Finally, numerical examples are given to illustrate the asymptotical meansquare stability under variable stepsize and transformation approach.
Severe abdominal pain in a septic child post open appendicectomy
Adam O'Connor
Shariq  Sabri

Adam O'Connor

and 2 more

May 23, 2020
Post appendicectomy abscess formation is uncommon in patients with non-perforated appendicitis. Diagnosis via imaging is essential to provide swift treatment and resolution of underlying infection, which we demonstrate in our case.
Atlanto-odontoid pyogenic arthritis revealing a Jugular Vein Thrombosis
Maroua SLOUMA
Abir Dghaies

Maroua SLOUMA

and 7 more

May 23, 2020
We report here the case of a 51-year-old man presented with inflammatory neck pain and fever. Inflammatory biomarkers were increased. The magnetic resonance imaging showed synovitis of atlanto-odontoid joint, anterior epidural collection, and cerebral vein thrombosis affecting sigmoid sinus and internal jugular venous.
Existence and controllability results for second-order neutral stochastic equations w...
Abbes Benchaabane
Ahmed Yahia Rakia

Abbes benchaabane

and 1 more

May 23, 2020
In this paper we consider a class of second-order impulsive stochastic functional differential equations driven simultaneously by a Rosenblatt process and standard Brownian motion in a Hilbert space. We prove an existence and uniqueness result under non-Lipschitz condition which is weaker than Lipschitz one and we establish some conditions ensuring the controllability for the mild solution by means of the Banach fixed point principle. At the end we provide a practical example in order to illustrate the viability of our result.\end{abstract}
MAJOR APPROACHES THE USE OF GH SECRETAGOGUE (MK-677) FOR MUSCLE MASS GAIN IN ELDERLY:...
Dr. Idiberto Jose Zotarelli Filho, MSc, Ph.D

Dr. Idiberto Jose Zotarelli Filho, MSc, Ph.D

May 23, 2020
Introduction: The number of disabilities due to age is expected to double by 2060. In this scenario, the development of sarcopenia is an important risk factor for the development of frailty, loss of independence and physical disability in the elderly and is associated with lower survival in critically ill patients. In this sense, the decline in fat-free mass correlates with the decline associated with the age of growth hormone (GH) secretion. Thus, GH secretagogue (MK-677) as the first orally active ghrelin mimetic may increase pulsatile GH secretion in the elderly. Objective: The main objectives were to determine whether oral MK-677 in healthy elderly would increase GH and IGF-I levels, prevent the decline of FFM and decrease abdominal visceral fat (AVF) with acceptable tolerability. Methods: A total of 18 articles were found involving MK-677, GH secretagogue, sarcopenia, insulin-like growth factor-1, safety, and efficacy. Initially, it was held the existing exclusion title and duplications following the interest described in this work. After this process, 5 articles were included and discussed in this study. The present study was elaborated according to the rules of systematic review- PRISMA (Transparent reporting of systematic reviews and meta-analysis- http://www.prisma-statement.org/). Results: In a clinical study, MK-677 neutralized three important factors contributing to the development of sarcopenia, which is reduced GH secretion, fat-free mass loss, and inadequate food intake. A recent study looked at the safety and efficacy of the oral GH secretagogue (MK-677) in humans, showing that MK-677 promotes pulsatile GH release that is subject to negative feedback and may prevent supra-therapeutic levels. of GH and its sequelae. Available studies indicate that MK-677 is well tolerated, however, there is a bias in decreased insulin sensitivity. There were no adverse effects attributable to MK-677. However, MK-677 had an unfavorable safety profile in individuals with congestive heart failure. Conclusion: The most confirmed sarcopenia treatment methods are nutritional overfeeding and resistance training, but studies have shown that supplementation with MK-677 can significantly reduce three important factors contributing to the development of sarcopenia, which is reduced secretion. GH loss, fat-free mass loss, and inadequate food intake, safely and effectively. However, it is imperative to increase randomized clinical trials to establish a consensus treatment. Keywords: MK-677. Ibutamoren. GH secretagogue. Sarcopenia. Elderly.
EVALUATION OF SALIVARY CORTISOL LEVELS DURING A LONG CROSSFIT® CHAMPIONSHIP
Dr. Idiberto Jose Zotarelli Filho, MSc, Ph.D

Dr. Idiberto Jose Zotarelli Filho, MSc, Ph.D

May 23, 2020
Objective: This study measured the cortisol levels of professional athletes during a CrossFit® championship. Then, it evaluated the physiological response caused by cortisol. Increased cortisol levels may interfere with the athletes’ performance and muscle recovery. Materials and Methods: A prospective observational cross-sectional study was performed with a sample of eight female professional athletes, aged between 20 and 34 years, enrolled in the 2017 Brazil CrossFit Championship (TCB), held in Valinhos, state of Sao Paulo, Brazil.  The salivary samples were obtained during the three days of the championship in two different moments: in the morning, before athletes’ warm-up, and 15 minutes after the last workout of each day. Results: Before warming up, the mean values of salivary cortisol were 15.9 ng/mL, 13.2 ng/mL, and 13.1 ng/mL, respectively. After the last workout, the mean values for cortisol were 6.4 ng/mL, 9.6 ng/mL, and 7.1 ng/mL, respectively. A statistically significant difference was found on the first day of competition.  The results presented the expected diurnal cycle of this hormone.  Conclusion: CrossFit® is a sport that alternates medium- to high-intensity exercises, including gymnastics, metabolic conditioning, and weight lifting. This competitive sport presents a variability of stressors, which may increase cortisol production and secretion according to different studies. This study found that the physiological stress of a CrossFit® championship affects the production of cortisol and increases the stimulation of the hypothalamic axis. However, the normal cortisol secretion response suggests a physiological adaptation or alteration in the cortisol receptor in the athletes studied.  Further studies carried out with a larger sample are necessary to assess these neuroendocrine changes.Keywords: CrossFit®. Cortisol. Physical activity. Women.
Incidence, clinical characteristics and outcomes of acute kidney injury in hospitalis...
Olga Laszczyńska
Ana Azevedo

Olga Laszczyńska

and 2 more

May 23, 2020
Background and aims: Acute kidney injury (AKI) is a common clinical syndrome that has been consistently linked with increased morbidity and mortality risk. Prognosis, as well as incidence, varies depending on patients characteristics and health care setting. We aimed to evaluate the incidence of AKI and related outcomes in a population of hospitalised patients taking into account the time of onset and severity of the syndrome. Methods: This retrospective study included adult patients admitted to a tertiary care hospital between January 1, 2013, and December 31, 2015, who had at least one inpatient serum creatinine (SCr). We distinguished between AKI apparent at admission (CA-) and afterwards during hospitalisation (HA-AKI). Results: The incidence of AKI was 15.2 %, of which 68% of episodes developed during hospital care. Baseline characteristics of CA-AKI and HA-AKI were similar, but CA-AKI patients were more likely to have more severe episodes and shorter length of stay than patients with HA-AKI (30.9% vs 14.5% with AKI stage 3 and 8.1 vs 14.8 days, respectively). We found a strong, gradual association (after multivariate adjustment) between stage of AKI and mortality. Irrespective the type of AKI, stage 3 was related to the five-fold risk of in-hospital death and a two-fold risk of death at the 6th-month in comparison to No AKI. Conclusions: One in six of hospitalised patients experienced AKI, and almost two-thirds of events developed during the hospital stay. There were no differences in short-term mortality between AKI type, but the risk of death related to the severity of the syndrome.
Modeling the effect of test-and-slaughter strategies to control bovine tuberculosis i...
Catalina Picasso Risso
Julio Alvarez

Catalina Picasso Risso

and 6 more

May 23, 2020
Bovine tuberculosis (bTB) prevalence substantially increased over the past two decades with relatively high impact on large dairy herds, raising the concern of regulatory authorities and industry stakeholders, and threatening animal and public health. Lack of resources, together with the economic and social consequences of whole-herd stamping-out, makes depopulation an impractical disease control alternative in these herds. The increase in bTB-prevalence was associated with demographic and management changes in the dairy industry in Uruguay, reducing the efficacy of the current control program (i.e. status quo) based on intradermal serial testing with caudal fold- and comparative cervical- tuberculin test-and slaughter of reactors (CFT-CCT). Here, we aimed to assess the epidemiological effectiveness of six alternative control scenarios based on test-and-slaughter of positive animals, using mathematical modeling to infer bTB-within-herd dynamics. We simulated six alternative control strategies consisting of testing adult cattle (>1 year) in the herd every three months using one test (in-vivo or in-vitro) or a combination in parallel of two tests (CFT, interferon-gamma release assay –IGRA- or Enzyme-linked immunosorbent assay). Results showed no significant differences overall in the time needed to reach bTB-eradication (median ranging between 61 to 82 months) or official bovine tuberculosis-free status (two consecutive negative herd-tests) between any of the alternative strategies and the status quo (median ranging between 50 and 59 months). However, we demonstrate how alternative strategies can significantly reduce bTB-prevalence when applied for restricted periods (6, 12, or 24 months), and in the case of IGRAc (IGRA using peptide-cocktail antigens), without incurring on higher unnecessary slaughter of animals (false-positives) than the status quo in the first 6 months of the program (P-value <0.05). Enhanced understanding bTB-within-herd dynamics with the application of different control strategies help to identify optimal strategies to ultimately improve bTB-control and -eradication from dairies in Uruguay and similar endemic settings.
The exponential behavior of 3D stochastic primitive equations driven by fractional no...
Lidan Wang
Guoli Zhou

Lidan Wang

and 2 more

May 23, 2020
In this article, we study the exponential behavior of 3D stochastic primitive equations driven by fractional noise. Since fractional Brownian motion is essentially different from Brownian motion, the standard method via classic stochastic analysis tools is not available. Here, we develop a method which is close to the method from dynamic system to show that the weak solutions to 3D stochastic primitive equations driven by fractional noise converge exponentially to the unique stationary solution of primitive equations. This method may be applied to other stochastic hydrodynamic equations and other noises including Brownian motion and Lévy noise.
Local well-posedness of compressible Radiation Hydrodynamic equations with density-de...
Hao Li
Yachun Li

Hao Li

and 1 more

May 23, 2020
In this paper, we consider the Cauchy problem for three-dimensional isentropic compressible radiation hydrodynamic equations with density-dependent viscosity coefficients. When the viscosity coefficients are given as power of density ($\rho^\delta$ with $\delta>1$), we establish the local-in-time existence of classical solutions containing a vacuum for large initial data. Here, we point out that the initial layer compatibility conditions are not necessary.
Dynamical analysis of fractional-order of IVGTT glucose-insulin interaction
Sayed Saber
Mansoor Alshehri

Sayed Saber

and 3 more

May 23, 2020
A document by Sayed Saber, written on Authorea.
On preservation of functions with exponential growth by certain Exponential operators
Nav Mishra
Naokant Deo

Nav Mishra

and 1 more

May 23, 2020
In this study, our aim is to provide a modification of the so-called Ismail-May operators that preserve exponential functions eAx, A ∈ ℝ. In consonance to this, we begin with estimating the convergence rate of the operators in terms of usual and exponential modulus of continuity. We also provide a global approximation and a quantitative Voronovskaya result. Moreover, to validate the modification, we exhibit some graphical representations using Mathematica software to compare the original operator and its modification. We conclude that the modified operators not only preserve exponential functions but also provide faster rate of convergence when A > 0.
Optical soliton solutions for the generalized Kudryashov's equation of propagation pu...
Elsayed Zayed
Mohamed Alngar

Elsayed Zayed

and 1 more

May 23, 2020
In this paper, we employ three integration algorithms namely, the well known Kudryashove method, the new Kudryashov method and the unified Riccati equation expansion method to extract optical soliton solutions for the generalized Kudryashov's equation with power nonlinearities. Straddled soliton, bright solitons, dark solitons and singular solitons have been found
A note on factored infinite series and trigonometric Fourier series
Huseyin  Bor

Hüseyin BOR

May 23, 2020
In this paper, we have proved two main theorems under more weaker conditions dealing with absolute weighted arithmetic mean summability factors of infinite series and trigonometric Fourier series. We have also obtained some new results for different absolute summability methods.
Analysis and Control of a Delayed HIV Infection Model with Cell-to-Cell Transmission...
Yu Liu
Xiaolin Lin

Yu Liu

and 2 more

May 23, 2020
Recent researches show that virus-to-cell infection and cell-to-cell transmission are two HIV infection modes. In this paper, we propose a delayed HIV infection model including both virus-to-cell infection and cell-to-cell transmission and CTL immune response. The time delay describes the phenomenon between viral entry and viral production. We show the nonnegativity and boundedness of solution, obtain the equilibrium points and prove local asymptotic stability of the equilibrium points. Then the optimal control problem with antiretroviral therapy and pharmacological delay is posed. We establish and analyze two types of objective functions, one is linear control and the other is quadratic control. Numerical simulations have been performed to verify the stability of equilibrium points and show the optimal control strategies and the effects of control on cells concentration by Matlab and Lingo.
Exponential stability of implicit numerical solution for nonlinear neutral stochastic...
Haoyi Mo
Linna Liu

Haoyi Mo

and 3 more

May 23, 2020
The aim of this work is to investigate the exponential mean-square stability for neutral stochastic differential equations with time-varying delay and Poisson jumps. We give some conditions that all the drift, diffusion and jumps coefficients can be nonlinear, to obtain the stability of the analytic solution. It is revealed that the implicit backward Euler-Maruyama numerical solution can reproduce the corresponding stability of the analytic solution under these nonlinear conditions. This is different from the explicit Euler-Maruyama numerical solution whose stability depends on the linear growth condition. With some requirements related to the delay function and the property of compensated Poisson process, we deal with time-varying delay and Poisson jumps. One highly nonlinear example is provided to confirm the effectiveness of our theory.
Primary Left Ventricular Leiomyosarcoma - A Case Report
Vipin Balachandran
Vanessa Young

Vipin Balachandran

and 3 more

May 23, 2020
Cardiac leiomyoscarcomas is a rare subset of the already infrequent primary malignant cardiac neoplastic spectrum. The most common site for a primary leiomyosarcoma is the right ventricle with fewer than five globally reported cases in the left ventricle. Most present with non-specific symptoms but attention is usually sought after the appearance of compressive symptoms or arrhythmias. We present the case of a left ventricular leiomyosarcoma that had a delayed diagnosis and its subsequent surgical management.
A Stuck Colonoscope in the Chest Cavity: An Uncommon Complication
Muhammad Usman Shah
Ahmed Eissa

Muhammad Usman Shah

and 3 more

May 23, 2020
Colonoscopy is generally considered a safe procedure, with a low rate of complications. Although rare, the migration of the colonoscope may represents a life-threating events, requiring emergency treatment. We herein describe the case of an elective colonoscopy complicated by an irretrievable colonoscope that migrated, through a previous traumatic diaphragmatic hernia, in the chest cavity. This hernia was likely a chronic complication of a previous abdominal trauma. Several attempts to retrieve the scope were unsuccessful. After further investigations and collegial discussion, a left thoracotomy was performed, with the aim to retrieve the colonoscope and to reduce the hernia.
A Novel Index Combining Diastolic and Systolic Tissue Doppler Parameters for Predicti...
Selma Arı
Hasan ARI

Selma Arı

and 5 more

May 23, 2020
Objective:Identification of patients who are nonresponders to cardiac resynchronization therapy (CRT) with the use of simple and objective parameters may be helpful in tailoring treatment. The aim of this study is to investigate whether E/(Ea×Sa) could be a predictor of CRT nonresponders (E=early diastolic transmitral velocity, Ea=early diastolic mitral annular velocity, Sa=systolic mitral annular velocity). Methods:In total, 53 heart failure patients were evaluated for this study, and 33 patients were included according to the study criteria. Before and six months after CRT-D(CRT with a defibrillator) implantation, E, Ea, and Sa were determined at the medial and lateral mitral annular sites, and the average values were obtained. E/(Ea×Sa) was calculated (medial, lateral, average). The patients were followed for six months to monitor their CRT response. A responder was defined as a patient with a reduction in end-systolic volume of <15% and an increase in six-minute walking distance of 50 meters. Results:At a six-month follow-up, 24(72.7%) of the 33 patients responded to CRT. At the six-month follow-up, in the responder group, the E/Ea ratio, lateral mitral, and average E/(Ea×Sa) indices were significantly reduced (p<0.01 for all). The baseline lateral mitral, medial mitral, and average E/(Ea×Sa) indices were significantly lower in the responder group than in the nonresponder group (p≤0.01 for all). The ROC analysis showed that all the E/(Ea×Sa) indices predict the CRT nonresponder patients. The AUC values were 0.89(lateral E/(Ea×Sa)), 0.85(average E/(Ea×Sa)), and 0.77(medial E/(Ea×Sa))(p≤0.01 for all). Conclusion:We found that the E/(Ea×Sa) index is a novel predictor of CRT nonresponder patients.
In Silico Process Development via Computational Modeling: Insights into Molecular Bio...
Francis  Insaidoo
John Welsh

Francis Insaidoo

and 4 more

May 23, 2020
The goal of this research is to leverage computational molecular biophysics to guide process development, reduce experimental burden and focus purification activities on feasible targets. Here, we distill a complex separation problem (e.g. chromatographic retention of monoclonal antibodies) into a tangible model (ligand/protein complex), which is computationally feasible while preserving enough detail (atomistic level for interaction site) to support industrially relevant separation challenges. Computational docking, coupled with molecular dynamics simulation, produces results that are directionally consistent with chromatography for proteins (mAb). This approach is generalizable and can be applied to a range of ligands (AEX, CEX, and Mixed Mode). A detailed model of the chromatography base matrix (agarose) was constructed to obtain a biophysical understanding of potential protein/base matrix interactions. The base matrix was then modified in silico with ligands over a range of ligand densities representative of commercial chromatography resins to generate an agarose/ligand complex. A generic approach was developed to model the impact of avidity and ligand density on mAb/ligand interaction. The results revealed that increasing ligand density mask contributions of base matrix binding. Increasing the number of ligands that can interact with mAb results in more favorable free energy of binding or ΔG (more negative) with a limited incremental increase in ΔG by increasing N (number of ligands per agarose cluster) above three. Additionally, for protein/ligand interactions at each binding site, not all ligands contribute equally to the binding affinities or interaction energies and a redistribution of binding interactions/energies occur as N increases. These observations yield insights into the impact of avidity on retention (macroscopic affinity measurement via k’). The generic approach described in this manuscript can be leveraged to inform resin selection and design as well as targeted ligand selection/purification development in a rational manner.
Drug Use Associated Tricuspid Valve Infective Endocarditis in Pregnancy
Dishen Lin
Clancy Mullan

Dishen Lin

and 9 more

May 23, 2020
We report a case of intravenous drug use-associated tricuspid valve endocarditis in a 28-year-old pregnant female at 26-weeks gestation. Despite appropriate intravenous antibiotics, the patient developed life-threatening complications and underwent planned cesarean delivery at 28 weeks 6 days gestation followed by interval tricuspid valve replacement one week later. Both the patient and her infant were successfully managed through the perioperative period.
Restoring Esthetics and Function in worn anterior teeth using Dahl Priniciple -- A Se...
Karthickraj M

Karthickraj M

May 23, 2020
Case series was done to discuss the use of cemented dahl appliance for increasing the occlusal vertical dimension (OVD) and effectively restore esthetics and function in worn anterior teeth.
Nonmetal Oxygen Vacancies for Catalysis under Cover
Qiuwen Liu
Qiang Liu

Qiuwen Liu

and 5 more

May 23, 2020
In heterogeneous catalysis, oxygen vacancies of metal oxides play a key role by modulating properties of coordination, electron states, electrical conductivity, and surface property. However, the investigation of oxygen vacancies in nonmetal oxides and their catalytic applications have rarely been reported. Here, we present oxygen vacancies-rich BPO4 hollow spheres covered by few-layer hexagonal boron nitride (BN) with a sandwich-like structure (BN@BPO4@BN) through an in-situ growth method. The as-prepared catalyst showed better catalytic activity and higher selectivity than that of commercial BN in the oxidative dehydrogenation of propane to propene because of the synergetic effect between oxygen vacancies-rich BPO4 and h-BN. Oxygen vacancies increase the adsorption amount of propane and the confined space at the interface of BN and BPO4 weakens the adsorption of propene, benefiting the recycle of active sites. Moreover, the confined space and oxygen vacancies result in the transformation of reaction kinetic model.
Risk assessment and prognostic aspect of coagulopathy in Coronavirus Disease 2019 (CO...
Mujibur Rahman
Nadira Naznin  Rakhi

MUJIBUR RAHMAN

and 1 more

May 22, 2020
Since December 2019, the rapid spread of SARS CoV-2 across the border, shuffled into a world pandemic situation with an alarming rate of morbidity and mortality. Concerns are mounting as the reports indicate tangled circumstances among the COVID-19 patients due to blood coagulopathy followed by organ dysfunction. COVID-19 induced an alteration in coagulation function increase the risk of pulmonary embolism and deep vein thrombosis associated with poor prognosis as well as high mortality. An elevated level D-dimer and other fibrin degrading protein are documented among the patients with COVID-19; especially in severe cases. Differences in coagulopathy among severe and non-severe cases, required prompt attention to adopt a more effective management strategy.
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