bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of cytokine concentrations in a trehalose‐stabilised lyophilised canine platelet product: a preliminary study
Authors: Goggs Robert , Cremer Signe , Brooks Marjory B.
Published: August 2020

Background

Platelet transfusion is indicated for haemorrhage due to severe thrombocytopenia and for trauma associated coagulopathy. Febrile non‐haemolytic transfusion reactions are a common complication of platelet transfusions in people and may be due to accumulated inflammatory cytokines. The present study aimed to determine the cytokine profile of a novel canine lyophilised platelet product following reconstitution, to assess the lyophilised platelets’ activation response to physiological platelet agonists and to compare the cytokine profiles of basal and stimulated canine lyophilised platelets.

Methods

Cell counts and biochemical analyses were conducted following reconstitution. Cytokine concentrations were measured with a canine‐specific multiplex immunocapture assay and with an electrochemiluminescent ELISA. Aliquots of reconstituted product from three separate vials were activated for 10 minutes under non‐stirred conditions using adenosine diphosphate, thrombin or convulxin and their cytokine concentrations compared with unactivated samples. Flow cytometry and light‐transmission aggregometry were used to evaluate the product’s ability to express a procoagulant surface, degranulate and aggregate. Fresh platelet‐rich plasma was used as a positive control.

Results

The product had a mean±SD particle count of 1.23±0.2×109 /ml, contained platelets that expressed surface phosphatidylserine before agonist stimulation and was capable of aggregation in response to thrombin stimulation suggesting that the product may have haemostatic potential following in vivo administration. Cytokine concentrations measured by the immunocapture assay were generally low, while twofold to threefold increases relative to published intervals were noted for several cytokines using the ELISA. Concentrations of chemokine (C‐X‐C) motif ligand 8 and tumour necrosis factor‐α were significantly increased as measured by the ELISA, but not by the immunocapture assay, while concentrations of KC‐like were significantly increased as measured by the immunocapture assay. Stimulation with platelet agonists did not affect measured cytokine concentrations.

Conclusion

Further study of the effects of administration of this lyophilised platelet product is warranted.
Polymorphism and consistency: Complex network based on execution trace of system calls in Linux kernels
Authors: Han Lihong , Zhou Qingguo , Zhang Juheng , Yang Xuhui , Zhou Rui , Tang Jianxin
Published: August 2020

Linux operating system (LOS) represents one of the most complex human-made systems, and it acts as an important function between software and hardware. In recent years, a large number of related works treat Linux operating system as a complex network and explore some of the unique characteristics of the network. However, there is little research on the execution process of LOS in terms of networks. In this paper, the run-time behaviors of execution process are traced by system calls of LOS kernel, and the run-time behaviors networks (RTBNs) are constructed, in which the nodes of RTBN represent the functions, and the edges of RTBN represent the function call relations. On this basis, the statistical characteristics of the RTBNs are investigated, and some features of the RTBNs are revealed. The result shows that some of the network characteristics remain relatively stable without obvious changes, showing the characteristics of consistency. However, some of the network characteristics tend to be random and uncertain, showing the feature of polymorphism.
Hybrid Hermite polynomial chaos SBP-SAT technique for stochastic advection-diffusion equations
Authors: Kaur Navjot , Goyal Kavita
Published: August 2020

The study of advection–diffusion equation has relatively became an active research topic in the field of uncertainty quantification (UQ) due to its numerous real life applications. In this paper, Hermite polynomial chaos is united with summation-by-parts (SBP) – simultaneous approximation terms (SATs) technique to solve the advection–diffusion equations with random Dirichlet boundary conditions (BCs). Polynomial chaos expansion (PCE) with Hermite basis is employed to separate the randomness, then SBP operators are used to approximate the differential operators and SATs are used to enforce BCs by ensuring the stability. For each chaos coefficient, time integration is performed using Runge–Kutta method of fourth order (RK4). Statistical moments namely mean and variance are computed using polynomial chaos coefficients without any extra computational effort. The method is applied on three test problems for validation. The first two test problems are stochastic advection equations on [Formula: see text] without any boundary and third problem is stochastic advection–diffusion equation on [0,2] with Dirichlet BCs. In case of third problem, we have obtained a range of permissible parameters for a stable numerical solution.
Hearts are Poised Near the Edge of Chaos
Authors: Zhang Xiaohong , Wu Zhengze , Chua Leon
Published: August 2020

The Cardiac Purkinje Fiber (CPF) is the last branch of the heart conduction system, which is meshed with the normal ventricular myocyte. Purkinje fiber plays a key role in the occurrence of ventricular arrhythmia and maintenance. Does the heart Purkinje fiber cells have the same memory function as the cerebral nerve? In this paper, the cardiac Hodgkin–Huxley equation is taken as the object of study. In particular, we find that the potassium ion-channel [Formula: see text] and the sodium ion-channel [Formula: see text] are memristors. We also derive the small-signal equivalent circuits about the equilibrium points of the CPF Hodgkin–Huxley model. According to the principle of local activity, the regions of Locally-Active domain, Edge of Chaos domain and Locally-Passive domain are partitioned under parameters [Formula: see text], and the domain exhibiting the normal human heartbeat frequency range (Goldilocks Zone) is identified. Meanwhile, the Super-Critical Hopf bifurcation of the CPF Hodgkin–Huxley model is identified. Finally, the migration changes between different state domains under external current [Formula: see text] excitation are analyzed in detail.

All of the above complex nonlinear dynamics are distilled and mapped geometrically into a surreal union of intersecting two-dimensional manifolds, dubbed the Hodgkin–Huxley’s magic roof.
Stability and Bifurcation in Discrete Mechanical Systems: An Experimental and Analytical Study
Authors: Guan Yue , Virgin Lawrence N.
Published: August 2020

The curse of dimensionality looms over many studies in science and engineering. Low-order systems provide conceptual clarity but often fail to reveal the extent of possible complexity, whereas high-order systems present a host of daunting challenges to the analyst, not least the classification and visualization of typical behavior. In this paper, we detail the behavior of systems that fall somewhere between a classification of low- and high-order.

[Formula: see text][Formula: see text]We present both theoretical and experimental investigations into the nonlinear behavior of a couple of mechanical systems with three mechanical/structural degrees-of-freedom (DOF), with a special focus on bifurcation and multiple equilibria. Useful insight is provided by observation of transient trajectories as they meander about and between equilibria, especially revealing the influence of unstable equilibria, not normally accessible in an experimental context. For instance, the influences of index-1 saddles are mainly detected in three aspects: determining the systems capability to snap-through by generating accessible snap-though tubes, attracting nearby trajectories temporarily oscillating around it, and separating adjacent trajectories. Iso-potentials are 3D-printed to present the energy landscape. For these systems, the 3D configuration space allows considerable complexity, but is also somewhat amenable to geometric interpretation. By varying a mass/stiffness ratio as a control parameter, bifurcation structures and morphing potential energy landscapes exhibiting up to 11 equilibria are obtained. Finally, analytical and experimental studies reveal that parametric excitations can stabilize some unstable equilibria under the right amplitudes and frequencies.
Detection of Dynamical Matching in a Caldera Hamiltonian System Using Lagrangian Descriptors
Authors: Katsanikas M. , García-Garrido Víctor J. , Wiggins S.
Published: August 2020

The goal of this paper is to apply the method of Lagrangian descriptors to reveal the phase space mechanism by which a Caldera-type potential energy surface (PES) exhibits the dynamical matching phenomenon. Using this technique, we can easily establish that the nonexistence of dynamical matching is a consequence of heteroclinic connections between the unstable manifolds of the unstable periodic orbits (UPOs) of the upper index-1 saddles (entrance channels to the Caldera) and the stable manifolds of the family of UPOs of the central minimum of the Caldera, resulting in the temporary trapping of trajectories. Moreover, dynamical matching will occur when there is no heteroclinic connection, which allows trajectories to enter and exit the Caldera without interacting with the shallow region of the central minimum. Knowledge of this phase space mechanism is relevant because it allows us to effectively predict the existence, and nonexistence, of dynamical matching. In this work, we explore a stretched Caldera potential by means of Lagrangian descriptors, allowing us to accurately compute the critical value for the stretching parameter for which dynamical matching behavior occurs in the system. This approach is shown to provide a tremendous advantage for exploring this mechanism in comparison to other methods from nonlinear dynamics that use phase space dividing surfaces.
Periodic Oscillations in the Quorum-Sensing System with Time Delay
Authors: Chen Menghan , Ji Jinchen , Liu Haihong , Yan Fang
Published: August 2020

The main aim of this paper is to study the oscillatory behaviors of gene expression networks in quorum-sensing system with time delay. The stability of the unique positive equilibrium and the existence of Hopf bifurcation are investigated by choosing the time delay as the bifurcation parameter and by applying the bifurcation theory. The explicit criteria determining the direction of Hopf bifurcation and the stability of bifurcating periodic solutions are developed based on the normal form theory and the center manifold theorem. Numerical simulations demonstrate good agreements with the theoretical results. Results of this paper indicate that the time delay plays a crucial role in the regulation of the dynamic behaviors of quorum-sensing system.
Realization of Arbitrary Configuration of Limit Cycles of Piecewise Linear Systems
Authors: Wang Shaoqing , Yang Jiazhong
Published: August 2020

In this paper, we consider the realization of configuration of limit cycles of piecewise linear systems on the plane. We show that any configuration of finite number of Jordan curves can be realized by a discontinuous piecewise linear system with two zones separated by a continuous curve.
Bifurcation and Potential Landscape of p53 Dynamics Depending on PDCD5 Level and ATM Degradation Rate
Authors: bi Yuanhong , Liu Quansheng , Wang Lixin , Yang Wuritu , Wu Xinwei
Published: August 2020

The dynamic behavior of the tumor suppressor p53 as an important signal in response to various stresses can influence cellular fate decisions. Programmed cell death 5 (PDCD5) and wild type p53-induced phosphatase 1 (Wip1) regulate p53 dynamics as its activator and inhibitor, respectively. In the present study, we add Wip1 to p53-Mdm2 (Murine double minute 2) module with PDCD5 and focus on p53 dynamics depending on PDCD5 and ataxia telangiectasia mutated (ATM) degradation rate regulated by Wip1. The bifurcation results reveal that p53 dynamics varies with these two parameters. p53 exhibits monostability and bistabiltiy for smaller and larger PDCD5 level while p53 shows oscillation or coexistence of oscillation and steady states in a narrow parameter range. These dynamics are further explored by time series and potential landscapes. Our results may be useful for regulating cell fate upon DNA damage.
On the Motion of the Pendulum in an Alternating, Sawtooth Force Field
Authors: Burov Alexander A. , Nikonov Vasily I.
Published: August 2020

The motion of the pendulum in a variable sawtooth force field is considered. For the “lower” equilibrium, the necessary stability conditions are investigated numerically, the results are presented in the form of an Ince–Strutt diagram. Using the Poincaré–Melnikov method separatrix splitting is studied analytically. Numerically, for some values of parameters, the nonlinear dynamics is studied using Poincaré maps, the regions of regular and chaotic behavior are revealed. The iterative method earlier proposed is used for the localization of periodic solutions, located inside the numerically identified “invariant tori”.
Stability and Turing Patterns in a Predator–Prey Model with Hunting Cooperation and Allee Effect in Prey Population
Authors: Song Danxia , Song Yongli , Li Chao
Published: August 2020

In this paper, we are concerned with a diffusive predator–prey model where the functional response follows the predator cooperation in hunting and the growth of the prey obeys the Allee effect. Firstly, the existence and stability of the positive equilibrium are explicitly determined by the local system parameters. It is shown that the ability of the hunting cooperation can affect the existence of the positive equilibrium and stability, and the intrinsic growth rate of the predator population does not affect the existence of the positive equilibrium, but affects the stability. Then the diffusion-driven Turing instability is investigated and the Turing bifurcation value is obtained, and we conclude that when the ability of the cooperation in hunting is weaker than some critical value, there is no Turing instability. The standard weakly nonlinear analysis method is employed to derive the amplitude equations of the Turing bifurcation, which is used to predict the types of the spatial patterns. And it is found that in the Turing instability region, with the parameter changing from approaching Turing bifurcation value to approaching Hopf bifurcation value, spatial patterns emerge from spot, spot-stripe to stripe. Finally, the numerical simulations are used to support the analytical results.
Bifurcations of Solitary Waves of a Simple Equation
Authors: Yang Jiaopeng , Liu Rui , Chen Yiren
Published: August 2020

In this paper, we consider a simple equation which involves a parameter [Formula: see text], and its traveling wave system has a singular line.

Firstly, using the qualitative theory of differential equations and the bifurcation method for dynamical systems, we show the existence and bifurcations of peak-solitary waves and valley-solitary waves. Specially, we discover the following novel properties:

(i) In the traveling wave system, there exist infinitely many periodic orbits intersecting at a point, or two points and passing through the singular line, and there is no singular point inside a homoclinic orbit. (ii) When [Formula: see text], in the equation there exist three types of bifurcations of valley-solitary waves including periodic wave, blow-up wave and double solitary wave. (iii) When [Formula: see text], in the equation there exist two types of bifurcations of valley-solitary wave including periodic wave and blow-up wave, but there is no double solitary wave bifurcation.

Secondly, we perform numerical simulations to visualize the above properties.

Finally, when [Formula: see text] and the constant wave speed equals [Formula: see text], we give exact expressions to the above phenomena.
Exact Peakon, Periodic Peakon and Pseudo-Peakon Solutions of the Rotation-Two-Component Camassa–Holm System
Authors: Li Jibin , Chen Guanrong , Zhou Yan
Published: August 2020

In this paper, the method of dynamical systems developed in [Li & Chen, 2007] is applied to the rotation-two-component Camassa–Holm system. Through qualitative analysis, under given parameter conditions, exact explicit solitary wave solution, pseudo-peakon solution, peakon and periodic peakon, as well as compacton solution, are obtained. Some parameter conditions constraints are derived for ensuring the existence of these solutions.
Origin Preserving Path Formulation for Multiparameter ℤ2-Equivariant Corank 2 Bifurcation Problems
Authors: Furter Jacques-Elie
Published: August 2020

A singularity theory, in the form of path formulation, is developed to analyze and organize the qualitative behavior of multiparameter [Formula: see text]-equivariant bifurcation problems of corank 2 and their deformations when the trivial solution is preserved as parameters vary. Path formulation allows for an efficient discussion of different parameter structures with a minimal modification of the algebra between cases. We give a partial classification of one-parameter problems. With a couple of parameter hierarchies, we show that the generic bifurcation problems are 2-determined and of topological codimension-0. We also show that the preservation of the trivial solutions is an important hypotheses for multiparameter bifurcation problems. We apply our results to the bifurcation of a cylindrical panel under axial compression.
A Comparative Study of Implicit and Explicit Composite Time Integration Schemes
Authors: Kim Wooram , Reddy J. N.
Published: August 2020

In this paper, a number of recently proposed implicit and explicit composite time integration schemes are reviewed and critically evaluated. To give suitable guidelines of using them in practical transient analyses of structural problems, numerical performances of these schemes are compared through illustrative examples. Meaningful insights into computational aspects of the composite schemes are also provided. In the discussion, the role of the splitting ratio of the recent composite schemes is also investigated through a different point of view, and similarities and differences of various composite schemes are also studied. It is shown that the explicit composite scheme proposed recently by the authors can noticeably increase the efficiency and the accuracy of linear and nonlinear transient analyses when compared with other well-known composite schemes.
Game Theory Cancer Models of Cancer Cell-Stromal Cell Dynamics using Interacting Particle Systems
Authors: Zheng Yinan , Sun Yusha , Torga Gonzalo , Pienta Kenneth , Austin Robert
Published: August 2020

We describe an evolutionary game theory model that has been used to predict the population dynamics of interacting cancer and stromal cells. We first consider the mean field case assuming homogeneous and nondiscrete populations. Interacting Particle Systems (IPS) are then presented as a discrete and spatial alternative to the mean field approach. Finally, we discuss cases where IPS gives results different from the mean field approach.
Falsely Elevated 25-Hydroxy-Vitamin D Levels in Patients with Hypercalcemia
Authors: Choi Moon Kyung , Putthapiban Prapaipan , Lekprasert Patamaporn
Published: August 2020

Symptomatic hypercalcemia is a commonly encountered clinical scenario. Though it is important to collect detailed history to find clinical clues connecting to the etiology of hypercalcemia, the diagnostic workup of hypercalcemia depends heavily on laboratory analysis. Accurate measurement of the parathyroid hormone and vitamin D levels is essential. However, commercial laboratory measurement of vitamin D levels can be erroneous in the setting of abundant paraprotein in the serum. One of the most common conditions that can cause an increased amount of paraproteins is multiple myeloma. We report 2 cases of falsely elevated 25-hydroxy-vitamin D levels in patients presenting with hypercalcemia and an underlying diagnosis of MM.
Focused echocardiography in COVID-19: An unusual case of acute right ventricular dysfunction
Authors: Cherian Nishant , Reynard Charles , Body Richard
Published: August 2020

Background

During the novel coronavirus disease 2019 (COVID-19) pandemic, rapid diagnostics have been frequently sought to quickly evaluate a patient’s condition. Lung ultrasound can provide an early glimpse into the disease process and its severity. The addition of focused echocardiography can be particularly helpful in the haemodynamically compromised patient to detect myocardial involvement and alternative diagnoses.

Case

We discuss here a 53-year-old patient who presented to the Emergency Department with hypoxia and hypotension. Bedside focused ultrasound revealed signs of COVID-19 pneumonia with evidence of right ventricular strain, initially thought to be due to massive pulmonary embolism. A computed tomography scan confirmed the findings on ultrasonography, but surprisingly did not demonstrate a pulmonary embolism.

Conclusion

Point-of-care ultrasound in COVID-19 aided the diagnosis of affected organs and helped categorise the type of shock in this patient; however, right ventricular dysfunction should be interpreted with caution and may not be due to a pulmonary embolism, as in this case.
Suicidal behaviours among adolescents from 90 countries: a pooled analysis of the global school-based student health survey
Authors: Campisi Susan C. , Carducci Bianca , Akseer Nadia , Zasowski Clare , Szatmari Peter , Bhutta Zulfiqar A.
Published: August 2020

Background

Understanding the burden and determinants of suicide during adolescence is key to achieving global health goals. We examined the prevalence and determinants of self-reported suicidal ideation and attempts among younger (13–15 years) and older adolescents (16–17 years).

Methods

Pooled prevalence estimates with 95% confidence interval, were calculated for suicide ideation and attempts for 118 surveys from 90 countries that administered the Global School-based Student Health Survey (GSHS) to adolescents (13–17 years of age) from 2003 to 2017. Indicators (including individual and social factors) associated with suicidal ideation and attempts were determined from multivariable linear regressions on key outcomes.

Results

The prevalence of suicidal ideation representing 397,299 adolescents (51.3% female) was significantly higher among girls than boys whereas attempts did not differ by age or sex. Being bullied, or having no close friends was associated with suicidal ideation among girls 13–15 years and 16–17 years, respectively. Among all boys, being in a fight and having no close friends was associated with suicidal ideation with the addition of serious injury for boys 13–15 years. Common to all younger adolescents was an association of suicide attempt with being bullied and having had a serious injury. Among young boys, having no close friends was an additional indicator for suicide attempt. Having no close friends was associated with suicide attempt in older adolescents with the addition to being bullied in older girls and serious injury in older boys.

Conclusions

Building positive social relationships with peers and avoiding serious injury appear key to suicide prevention strategies for vulnerable adolescents. Targeted programs by age group and sex for such indicators could improve mental health during adolescence in low and middle-income countries, given the diverse risk profiles for suicidal ideation and attempts.
Advanced lipoprotein profile disturbances in type 1 diabetes mellitus: a focus on LDL particles
Authors: Amor Antonio J. , Castelblanco Esmeralda , Hernández Marta , Gimenez Marga , Granado-Casas Minerva , Blanco Jesús , Soldevila Berta , Esmatjes Enric , Conget Ignacio , Alonso Nuria , Ortega Emilio , Mauricio Didac
Published: August 2020

Background

Lipoprotein disturbances have been associated with increased cardiovascular disease (CVD) risk in type 1 diabetes mellitus (T1DM). We assessed the advanced lipoprotein profile in T1DM individuals, and analysed differences with non-diabetic counterparts.

Methods

This cross-sectional study involved 508 adults with T1DM and 347 controls, recruited from institutions in a Mediterranean region of Spain. Conventional and advanced (assessed by nuclear magnetic resonance [NMR] spectroscopy) lipoprotein profiles were analysed. Crude and adjusted (by age, sex, statin use, body mass index and leukocyte count) comparisons were performed.

Results

The median (interquartile range) age of the study participants was 45 (38–53) years, 48.2% were men. In the T1DM group, the median diabetes duration was 23 (16–31) years, and 8.1% and 40.2% of individuals had nephropathy and retinopathy, respectively. The proportion of participants with hypertension (29.5 vs. 9.2%), and statin use (45.7% vs. 8.1%) was higher in the T1DM vs. controls (p < 0.001). The T1DM group had a better conventional (all parameters, p < 0.001) and NMR-lipid profile than the control group. Thus, T1DM individuals showed lower concentrations of atherogenic lipoproteins (VLDL-particles and LDL-particles) and higher concentrations of anti-atherogenic lipoproteins (HDL-particles) vs. controls, even after adjusting for several confounders (p < 0.001 for all). While non-diabetic women had a more favourable lipid profile than non-diabetic men, women with T1DM had a similar concentration of LDL-particles compared to men with T1DM (1231 [1125–1383] vs. 1257 [1128–1383] nmol/L, p = 0.849), and a similar concentration of small-LDL-particles to non-diabetic women (672.8 [614.2–733.9] vs. 671.2 [593.5–761.4] nmol/L, respectively; p = 0.790). Finally, T1DM individuals showed higher discrepancies between NMR-LDL-particles and conventional LDL-cholesterol than non-diabetic subjects (prevalence of LDL-cholesterol < 100 mg/dL & LDL-particles > 1000 nmol/L: 38 vs. 21.2%; p < 0.001). All these differences were largely unchanged in participants without lipid-lowering drugs (T1DM, n = 275; controls, n = 317).

Conclusions

Overall, T1DM participants showed a more favourable conventional and NMR-lipid profile than controls. However, the NMR-assessment identified several lipoprotein derangements in LDL-particles among the T1DM population (higher discrepancies in NMR-LDL-particles vs. conventional LDL-cholesterol; a worse profile in T1DM women) that were overlooked in the conventional analysis. Further studies are needed to elucidate their role in the development of CVD in this population.
Dietary habits associated with growth development of children aged < 5 years in the Nouna Health and Demographic Surveillance System, Burkina Faso
Authors: Mank Isabel , Vandormael Alain , Traoré Issouf , Ouédraogo Windpanga Aristide , Sauerborn Rainer , Danquah Ina
Published: August 2020

Background

Knowing which dietary habits are associated with child growth could lead to better long-term health outcomes and improve the design of food-based interventions. We aimed to identify dietary habits that are associated with the growth development of children aged < 5 years living in rural Burkina Faso.

Methods

This study used cross-sectional baseline data from 514 children (8–59 months) within the Nouna Health and Demographic Surveillance System (HDSS) in 2018. Household socio-demographics and child dietary habits, height and weight were assessed. We constructed scores for dietary diversity (DDS) and food variety (FVS), and extracted exploratory dietary pattern scores (DPS) using principal component analysis (PCA). Child growth was measured using height-for-age (HAZ) and weight-for-height z-scores (WHZ). We used multiple-adjusted linear regressions considering for socio-economic factors to quantify associations.

Results

In this study population (median 36 ± 14 months old), stunting (HAZ < − 2) was seen in 26% and wasting (WHZ < − 2) in 7%. The DDS (median 7 ± 2 food groups) was positively associated with WHZ, while the FVS (median 13 ± 8 food items) was inversely associated with HAZ. We identified 4 dietary patterns: leaves-based, beans and poultry-based, maize and fish-based, and millet and meat-based diets. Only the maize and fish-based diet showed a statistically significant and here positive trend for associations with WHZ.

Conclusion

Growth development of children aged < 5 years continues to be a health problem in the Nouna HDSS. A higher dietary diversity and food variety and dietary patterns characterized by maize and fish and beans and poultry intake appear to be beneficial for growth of young children in this area.
Chemotherapy is not necessary for early-stage serous and endometrioid ovarian cancer after undergoing comprehensive staging surgery
Authors: Li Shuqing , Zhu Zhiling
Published: August 2020

In order to investigate whether adjuvant chemotherapy is essential for patients with early-stage serous and endometrioid epithelial ovarian cancer, the present study collected data from the US Surveillance, Epidemiology and End Results database between 2004 and 2015. All subjects underwent comprehensive staging surgery and were diagnosed as stages IA-IIA, grade 1–2. A total of 2644 patients were enrolled in the present study, among which 1589 patients received platinum-based chemotherapy. Comparisons of categorical data were performed via χ2 tests. Variables with P < 0.05 in univariate analyses were further analyzed using multiple logistic regression. Selection bias from the heterogeneity of demographic and clinical characteristics was avoided using propensity score matching. Cox proportional hazards models were applied to estimate hazard ratios (HRs) and 95% confidence intervals (CIs), investigating the association between variables and 5-year overall survival. After the propensity score matching, there was an equal number of patients with or without chemotherapy (n = 925). The results of the present study indicated that those aged ≥65 years were at an increased risk of ovarian cancer, and the age was associated with poor prognosis (HR, 1.486; CI, 1.208–1.827; P < 0.001). Endometrioid carcinoma was associated with improved 5-year overall survival compared with serous cystadenocarcinoma (HR, 0.697; CI, 0.584–0.833; P < 0.001). Chemotherapy could not prolong the 5-year overall survival of patients with early-stage serous and endometrioid ovarian cancer (HR, 1.092; CI, 0.954–1.249; P = 0.201). These results demonstrated that adjuvant chemotherapy was unnecessary for patients with early-stage serous and endometrioid ovarian cancer after they underwent comprehensive staging surgery.
Formula of compressibility and using it for air, noble gases, some hydrocarbons gases, some diatomic simple gases and some other fluids
Authors: Al-Raeei Marwan , El-Daher Moustafa Sayem
Published: August 2020

Based on solutions of the Ornstein–Zernike equation (OZE) of Lennard–Jones potential for mean spherical approximation (MSA), we derive analytical formula for the compressibility assuming that the system is of low density, homogeneous, isotropic and composed of one component. Depending on this formula, we find the values of the bulk modulus and the compressibility of air at room temperature and the bulk modulus and the compressibility of Methane, Ethylene, Propylene and Propane at nine per ten of critical temperature of each hydrocarbon. Also, we find the speed of sound in the air at various temperatures, the speed of sound in each of Helium, Neon, Argon, Krypton, Xenon, Methane, Ethylene, Propylene, Propane, Hydrogen, Nitrogen, Fluorine, Chlorine, Oxygen, Nitrous oxide (laughing gas), Carbon dioxide, Nitric oxide, Carbon monoxide, Sulphur dioxide and dichlorodifluoromethane at room temperature. Besides, we find the speed of sound in Methane, Ethylene, Propylene and Propane at nine per ten of critical temperature of each hydrocarbons depending on the formula we find. We show that the simple formula we derive in this work is reliable and agrees with the results obtained from other studies and literatures. We believe it can be used for many systems which are in low densities and described by Lennard–Jones potential.
Comparative transcriptome analyses define genes and gene modules differing between two Populus genotypes with contrasting stem growth rates
Authors: Han Xiao , An Yi , Zhou Yangyan , Liu Chao , Yin Weilun , Xia Xinli
Published: August 2020

Background

Wood provides an important biomass resource for biofuel production around the world. The radial growth of tree stems is central to biomass production for forestry and biofuels, but it is challenging to dissect genetically because it is a complex trait influenced by many genes. In this study, we adopted methods of physiology, transcriptomics and genetics to investigate the regulatory mechanisms of tree radial growth and wood development.

Results

Physiological comparison showed that two Populus genotypes presented different rates of radial growth of stems and accumulation of woody biomass. A comparative transcriptional network approach was used to define and characterize functional differences between two Populus genotypes. Analyses of transcript profiles from wood-forming tissue of the two genotypes showed that 1542, 2295 and 2110 genes were differentially expressed in the pre-growth, fast-growth and post-growth stages, respectively. The co-expression analyses identified modules of co-expressed genes that displayed distinct expression profiles. Modules were further characterized by correlating transcript levels with genotypes and physiological traits. The results showed enrichment of genes that participated in cell cycle and division, whose expression change was consistent with the variation of radial growth rates. Genes related to secondary vascular development were up-regulated in the faster-growing genotype in the pre-growth stage. We characterized a BEL1-like (BELL) transcription factor, PeuBELL15, which was up-regulated in the faster-growing genotype. Analyses of transgenic Populus overexpressing as well as CRISPR/Cas9-induced mutants for BELL15 showed that PeuBELL15 improved accumulation of glucan and lignin, and it promoted secondary vascular growth by regulating the expression of genes relevant for cellulose synthases and lignin biosynthesis.

Conclusions

This study illustrated that active division and expansion of vascular cambium cells and secondary cell wall deposition of xylem cells contribute to stem radial increment and biomass accumulation, and it identified relevant genes for these complex growth traits, including a BELL transcription factor gene PeuBELL15. This provides genetic resources for improving and breeding elite genotypes with fast growth and high wood biomass.
Associations of childhood exposure to malaria with cognition and behavior outcomes: a systematic review protocol
Authors: Ssemata Andrew Sentoogo , Nakitende Jacquelline Ann , Kizito Simon , Whipple Elizabeth C. , Bangirana Paul , Nakasujja Noeline , John Chandy C. , McHenry Megan S.
Published: August 2020

Background

Malaria is one of the major contributing risk factors for poor development of children living in low- and middle-income countries (LMICs). However, little is known about the specific domains of cognition and behavior that are impacted by malaria, the extent of these deficits, and the different types of the malaria spectrum that are associated with these deficits. The objective of this systematic review is to determine the association of the different types of malaria infection on cognition and behavioral outcomes among children living in LMICs.

Methods and analysis

We will systematically search online bibliographic databases including MEDLINE (via PubMed), CINAHL (via EBSCO), PsycINFO (via EBSCO), Embase, and The Cochrane Central Register of Controlled Trials (CENTRAL) as well as Google Scholar and bibliographies of pertinent articles. We will include studies with a comparison group (e.g., clinical trials, cohort, observational, cross-sectional case–control, and controlled before and after or interrupted–time–series studies) involving children under 18 years of age living in LMICs, as determined by the World Bank criteria, with either an active malaria infection or history of malaria. Included articles must also measure cognitive and/or behavior outcomes determined by standardized psychological assessments (questionnaire-based scales and or neurocognitive assessments). Studies will be excluded if they are not in English, lack a control group, take place in a high-income country, or if a standardized instrument was not used. Two reviewers will independently review all articles to determine if they meet eligibility criteria. Any conflicts will be resolved after discussion with a third reviewer. When a list of included articles is finalized, two reviewers will extract data to populate and then cross check within an electronic table. Risk of bias and the strength of evidence and recommendations will be assessed independently using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria, and a final score will be given upon consensus. For sufficiently homogeneous data on measured outcomes in multiple studies, we will investigate the possibility of pooling data to perform a meta-analysis.

Discussion

This systematic review will evaluate the evidence of the association of malaria on the cognitive and behavioral outcomes. Findings from this planned review will generate insight on the domains affected by the different forms of malaria infection and may inform subsequent malaria interventions and future research in pediatric care.

Systematic review registration

PROSPERO CRD42020154777
Don’t click: towards an effective anti-phishing training. A comparative literature review
Authors: Jampen Daniel , Gür Gürkan , Sutter Thomas , Tellenbach Bernhard
Published: August 2020

Email is of critical importance as a communication channel for both business and personal matters. Unfortunately, it is also often exploited for phishing attacks. To defend against such threats, many organizations have begun to provide anti-phishing training programs to their employees. A central question in the development of such programs is how they can be designed sustainably and effectively to minimize the vulnerability of employees to phishing attacks. In this paper, we survey and categorize works that consider different elements of such programs via a clearly laid-out methodology, and identify key findings in the technical literature. Overall, we find that researchers agree on the answers to many relevant questions regarding the utility and effectiveness of anti-phishing training. However, we identified influencing factors, such as the impact of age on the success of anti-phishing training programs, for which mixed findings are available. Finally, based on our comprehensive analysis, we describe how a well-founded anti-phishing training program should be designed and parameterized with a set of proposed research directions.
Cloud spot instance price prediction using kNN regression
Authors: Liu Wenqiang , Wang Pengwei , Meng Ying , Zhao Caihui , Zhang Zhaohui
Published: August 2020

Cloud computing can provide users with basic hardware resources, and there are three instance types: reserved instances, on-demand instances and spot instances. The price of spot instance is lower than others on average, but it fluctuates according to market demand and supply. When a user requests a spot instance, he/she needs to give a bid. Only if the bid is not lower than the spot price, user can obtain the right to use this instance. Thus, it is very important and challenging to predict the price of spot instance. To this end, we take the most popular and representative Amazon EC2 as a testbed, and use the price history of its spot instance to predict future price by building a k-Nearest Neighbors (kNN) regression model, which is based on our mathematical description of spot instance price prediction problem. We compare our model with Linear Regression (LR), Support Vector Machine Regression (SVR), Random Forest (RF), Multi-layer Perception Regression (MLPR), gcForest, and the experiments show that our model outperforms the others.
Bioleaching of Zn from sphalerite using Leptospirillum ferriphilum isolate: effect of temperature and kinetic aspects
Authors: Sundramurthy Venkatesa Prabhu , Rajoo Baskar , Srinivasan Natesan Rajendran , Kavitha Rajan
Published: August 2020

Biological methods for leaching of nonferrous and noble metals from its sulfide ores are widely applied at industrial enterprises of different countries. This process is based on the use of the oxidative activity of acidophilic microorganisms. Since all bio systems are quite sensitive to the temperature, bacterial leaching process also significantly effects. In the present study, the impact of temperature on bacterial leaching of Zn from its sulphide ore, sphalerite, was investigated using ore adapted iron oxidizing bacteria. The bacteria were isolated from mine drainage samples and subjected to gene sequencing. The acquired nucleotide sequence revealed that the isolate was Leptospirillum ferriphilum. The nucleotide sequence of L. ferriphilum isolate was submitted to National Center for Biotechnology Information (NCBI) and accession number KF743135 was assigned. Using the isolate, the Zn leaching data were collected in the 298–318 K temperature range. The results showed that leaching of Zn increases with temperature until optimum temperature of 313 K and achieves highest leaching efficiency of 96.96% within 20 days. Since bioleaching of minerals have become increasingly applied in different mining industries, there is immense important to analyze mechanistically-based kinetics for the design, optimization, operation, and control of biochemical processes. The kinetic study showed that the rate of Zn leaching was maximized at the optimum temperature. Further, the leaching data were analyzed using shrinking core model which revealed that the rate of leaching was inhibited by diffusion through product layer. Reaction kinetics is also to be contrasted with thermodynamics. Using Arrhenius law of thermodynamics, it was found that activation energy for Zn bioleaching reaction was 39.557 kJ mol−1. Such investigations will be necessitated for designing and implanting the ideal bioleaching system for metal bio-mining industries.
Influence of the polar light cycle on seasonal dynamics of an Antarctic lake microbial community
Authors: Panwar Pratibha , Allen Michelle A. , Williams Timothy J. , Hancock Alyce M. , Brazendale Sarah , Bevington James , Roux Simon , Páez-Espino David , Nayfach Stephen , Berg Maureen , Schulz Frederik , Chen I-Min A. , Huntemann Marcel , Shapiro Nicole , Kyrpides Nikos C. , Woyke Tanja , Eloe-Fadrosh Emiley A. , Cavicchioli Ricardo
Published: August 2020

Background

Cold environments dominate the Earth’s biosphere and microbial activity drives ecosystem processes thereby contributing greatly to global biogeochemical cycles. Polar environments differ to all other cold environments by experiencing 24-h sunlight in summer and no sunlight in winter. The Vestfold Hills in East Antarctica contains hundreds of lakes that have evolved from a marine origin only 3000–7000 years ago. Ace Lake is a meromictic (stratified) lake from this region that has been intensively studied since the 1970s. Here, a total of 120 metagenomes representing a seasonal cycle and four summers spanning a 10-year period were analyzed to determine the effects of the polar light cycle on microbial-driven nutrient cycles.

Results

The lake system is characterized by complex sulfur and hydrogen cycling, especially in the anoxic layers, with multiple mechanisms for the breakdown of biopolymers present throughout the water column. The two most abundant taxa are phototrophs (green sulfur bacteria and cyanobacteria) that are highly influenced by the seasonal availability of sunlight. The extent of the Chlorobium biomass thriving at the interface in summer was captured in underwater video footage. The Chlorobium abundance dropped from up to 83% in summer to 6% in winter and 1% in spring, before rebounding to high levels. Predicted Chlorobium viruses and cyanophage were also abundant, but their levels did not negatively correlate with their hosts.

Conclusion

Over-wintering expeditions in Antarctica are logistically challenging, meaning insight into winter processes has been inferred from limited data. Here, we found that in contrast to chemolithoautotrophic carbon fixation potential of Southern Ocean Thaumarchaeota, this marine-derived lake evolved a reliance on photosynthesis. While viruses associated with phototrophs also have high seasonal abundance, the negative impact of viral infection on host growth appeared to be limited. The microbial community as a whole appears to have developed a capacity to generate biomass and remineralize nutrients, sufficient to sustain itself between two rounds of sunlight-driven summer-activity. In addition, this unique metagenome dataset provides considerable opportunity for future interrogation of eukaryotes and their viruses, abundant uncharacterized taxa (i.e. dark matter), and for testing hypotheses about endemic species in polar aquatic ecosystems.
Identification of predation events in wild fish using novel acoustic transmitters
Authors: Weinz Amy A. , Matley Jordan K. , Klinard Natalie V. , Fisk Aaron T. , Colborne Scott F.
Published: August 2020

Background

Acoustic telemetry is a commonly used tool to gain knowledge about aquatic animal ecology through the study of their movements. In telemetry studies researchers must make inferences regarding the movements and the fates of tagged animals. Until recently, predation has been inferred in telemetry data using a variety of methods including abrupt changes in movement patterns or habitat use. An acoustic telemetry transmitter has been developed to detect predation events of tagged animals, and while they have performed well in controlled laboratory trials, literature regarding the application of these novel transmitters in field settings is limited. The objective of this research was to describe the detection data obtained from field studies using predation tags and propose methods to incorporate this information in decision-making about the fate of tagged animals. We implanted 60 yellow perch (Perca flavescens) with predation transmitters and evaluated their spatial use in a receiver array (34 ha) using a combination of centres of activity, roaming indices, and step length measures to examine detection data.

Results

Over 5 months, 19 apparent predation events were identified by the transmitters. Roaming indices and centres of activity revealed a variety of detection patterns, including instances of altered behaviour before and after predation that matched tag-indentified predation events, dropped tags post-predation, and detections that ceased post-predation indicating the predator might have left the array. Based on the observed patterns, probable predation was inferred for 15 of 19 triggered tags, with unclear fates for four fish.

Conclusions

Our study provided a framework to assess the fate of animals tagged with predation transmitters and demonstrate how these tags can contribute to telemetry studies. We showed how detections can be categorized using tag status to compare movement metrics among individuals, provided tools to explore space use surrounding predation events, and synthesized this information to inform uncertainty surrounding tag-identified predation events. Predation tags do not remove all uncertainty about the fate of tagged individuals, but combined with other metrics they increase the likelihood of identifying abnormal movements that could otherwise introduce biased detection histories into studies of small-sized fishes.