bluuebunny/crossref_metadata_2025 huggingface dataset:
Host-Induced Genome Instability Rapidly Generates Phenotypic Variation across Candida albicans Strains and Ploidy States
Authors: Smith Amanda C. , Hickman Meleah A.
Published: June 2020

Candida albicans
is an opportunistic fungal pathogen of humans. The ability to generate genetic variation is essential for adaptation and is a strategy that
C. albicans
and other fungal pathogens use to change their genome size. Stressful environments, including the host, induce
C. albicans
genome instability. Here, we investigated how
C. albicans
genetic background and ploidy state impact genome instability, both
in vitro
and in a host environment. We show that the host environment induces genome instability, but the magnitude depends on
C. albicans
genetic background. Furthermore, we show that tetraploid
C. albicans
is highly unstable in host environments and rapidly reduces in genome size. These reductions in genome size often resulted in reduced virulence. In contrast, diploid
C. albicans
displayed modest host-induced genome size changes, yet these frequently resulted in increased virulence. Such studies are essential for understanding how opportunistic pathogens respond and potentially adapt to the host environment.
Supplemental Material: Noble metal nanonugget insolubility in geological sulfide liquids
Authors: Anenburg Michael , Mavrogenes John
Published: June 2020

Detailed experimental and analytical methods, high-resolution versions of Figures 1 and 2, and the LA-ICP-MS data set including the R code used to generate Figure 2.
SD-OCT peripapillary nerve fibre layer and ganglion cell complex parameters in glaucoma: principal component analysis
Authors: Pazos Marta , Biarnés Marc , Blasco-Alberto Andrés , Dyrda Agnieszka , Luque-Fernández Miguel Ángel , Gómez Alicia , Mora Clara , Milla Elena , Muniesa MªJesús , Antón Alfonso , Díaz-Alemán Valentín Tinguaro
Published: June 2020

Background/aims

To identify objective glaucoma-related structural features based on peripapillary (p) and macular (m) spectral domain optical coherence tomography (SD-OCT) parameters and assess their discriminative ability between healthy and glaucoma patients.

Methods

Two hundred and sixty eyes (91 controls and 169 glaucoma) were included in this prospective study. After a complete examination, all participants underwent the posterior pole and the peripapillary retinal nerve fibre layer (pRNFL) protocols of the Spectralis SD-OCT. Principal component analysis (PCA), a data reduction method, was applied to identify and characterise the main information provided by the ganglion cell complex (GCC). The discriminative ability between healthy and glaucomatous eyes of the first principal components (PCs) was compared with that of conventional SD-OCT parameters (pRNFL, macular RNFL (mRNFL), macular ganglion cell layer (mGCL)and macular inner plexiform layer (mIPL)) using 10-fold cross-validated areas under the curve (AUC).

Results

The first PC explained 58% of the total information contained in the GCC and the pRNFL parameters and was the result of a general combination of almost all variables studied (diffuse distribution). Other PCs were driven mainly by pRNFL and mRNFL measurements. PCs and pRNFL had similar AUC (0.95 vs 0.96, p=0.88), and outperformed the other structural measurements: mRNFL (0.91, p=0.002), mGCL (0.92, p=0.02) and mIPL (0.92, p=0.0001).

Conclusions

PCA identified a diffuse representation of the papillary and macular SD-OCT parameters as the most important PC to summarise structural data in healthy and glaucomatous eyes. PCs and pRNFL parameters showed the greatest discriminative ability between healthy and glaucoma cases.
Evaluating the quality of systematic reviews and meta-analyses published on direct oral anticoagulants in the past 5 years
Authors: Eshaghpour Ali , Li Allen , Javidan Arshia Pedram , Chen Natalie , Yang Sarah , Crowther Mark Andrew
Published: June 2020

Systematic reviews (SRs) have been reported with increasing frequency as a means of collating studies which may have been performed over different period of times, in different geographical areas and by different groups of investigators. As SRs have become more common, quality metrics such as Assessing the Methodological Quality of Systematic Reviews (AMSTAR) have become available for these reviews. AMSTAR is an 11-point checklist that assesses the methodological and reporting quality of a SR. In clinical practice, direct oral anticoagulants (DOACs) have been increasingly used for the treatment and prevention of both venous and arterial thromboembolism. We sought to evaluate the quality of SRs published on DOACs using the AMSTAR criteria. A comprehensive search of Medline, EMBASE and the Cochrane Database of Systematic Reviews from January 2013 to February 2019 was performed. Two reviewers independently screened titles and abstracts and subsequently full texts for eligibility. Data extraction was also completed in duplicate. Categories of extracted data included AMSTAR rating, journal of publication, year of publication, number of studies included in the SR, reporting adherence to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, number of times the paper was cited and journal impact factor. A total of 3729 articles were identified, of which 250 were eligible for analysis. SR quality was highly variable with mean (SD) AMSTAR score of 5.68/11 (2.21). Reporting adherence to PRISMA guideline correlated with a moderate (5–8) or high quality (9–11) (OR=4.19, p<0.01) AMSTAR score. The methodological quality of DOACs was generally rated to be low-moderate, and improved adherence to AMSTAR methodological practices are strongly recommended.
Epidemiology and outcomes of gastroparesis, as documented in general practice records, in the United Kingdom
Authors: Ye Yizhou , Jiang Baoguo , Manne Sudhakar , Moses Peter L , Almansa Cristina , Bennett Dimitri , Dolin Paul , Ford Alexander C
Published: June 2020

Objective

To generate real-world evidence for the epidemiology of gastroparesis in the UK, we evaluated the prevalence, incidence, patient characteristics and outcomes of gastroparesis in the Clinical Practice Research Datalink (CPRD) database.

Design

This was a retrospective, cross-sectional study. Prevalence and incidence of gastroparesis were evaluated in the CPRD database, with linkage to Hospital Episodes Statistics Admitted Patient Care and Office for National Statistics mortality data. Prevalence and incidence were age and sex standardised to mid-2017 UK population estimates. Descriptive analyses of demographics, aetiologies, pharmacological therapies and mortality were conducted.

Results

Standardised prevalence of gastroparesis, as documented in general practice records, was 13.8 (95% CI 12.6 to 15.1) per 100 000 persons in 2016, and standardised incidence of gastroparesis rose from 1.5 (95% CI 1.1 to 1.8) per 100 000 person-years in 2004 to 1.9 (95% CI 1.4 to 2.3) per 100 000 person-years in 2016. The most common disease aetiologies were idiopathic (39.4%) and diabetic gastroparesis (37.5%), with a similar distribution of type 1 and type 2 diabetes among the 90% who had type of diabetes documented. Patients with diabetic gastroparesis had a significantly higher risk of mortality than those with idiopathic gastroparesis after diagnosis (adjusted HR 1.9, 95% CI 1.2 to 3.0). Of those with gastroparesis, 31.6% were not offered any recognised pharmacological therapy after diagnosis.

Conclusion

This is, to our knowledge, the first population-based study providing data on epidemiology and outcomes of gastroparesis in Europe. Further research is required to fully understand the factors influencing outcomes and survival of patients with gastroparesis.
Physical, emotional and sexual violence faced by spouses in India: evidence on determinants and help-seeking behaviour from a nationally representative survey
Authors: Krishnamoorthy Yuvaraj , Ganesh Karthika , Vijayakumar Karthiga
Published: June 2020

Objective

The current study was done to determine the prevalence, determinants, disclosure status and help-seeking behaviour of spousal violence using a nationally representative sample of ever-married women in India.

Methods

We have analysed the most recent National Family Health Survey-4 data (2015–2016) gathered from the Demographic Health Survey programme. Stratification and clustering in the sample design were accounted usingsvysetcommand. Point estimates were reported as proportions with 95% CI.

Results

A total of 66 013 ever-married women aged 15–49 years were included. Lifetime prevalence of spousal violence in India was 31% (95% CI 30.4% to 31.7%). Physical violence was the most common form accounting for 27.4% of victims followed by emotional (12.7%) and sexual violence (6.7%). Higher women’s age, Muslim religion, low education, employed women, lower socioeconomic status, presence of substance use among women and husbands, lower education and unemployed husbands, history of family violence and women in Central and Eastern states had a significant association with one or more forms of spousal violence with significant p value. Prevalence of help-seeking behaviour among women who faced spousal violence in India was 13.5% (95% CI 12.8% to 14.2%). Widowed/separated/divorced women, employed and highly educated women, and women in Northern states had significantly higher prevalence of help-seeking behaviour with respect to all the forms of spousal violence (p<0.001).

Conclusion

One in three women in India faces spousal violence. Only 1 in 10 women seeks help following violence. Efforts should be made to ensure people working in formal institutions screen for spousal violence and know how to respond to women facing it.
TFEB is a master regulator of tumor-associated macrophages in breast cancer
Authors: Li Yong , Hodge Johnie , Liu Qing , Wang Junfeng , Wang Yuzhen , Evans Trent D , Altomare Diego , Yao Yongzhong , Murphy E Angela , Razani Babak , Fan Daping
Published: June 2020

Background

Tumor-associated macrophages (TAMs) play key roles in the development of many malignant solid tumors including breast cancer. They are educated in the tumor microenvironment (TME) to promote tumor growth, metastasis, and therapy resistance. However, the phenotype of TAMs is elusive and how to regulate them for therapeutic purpose remains unclear; therefore, TAM-targeting therapies have not yet achieved clinical success. The purposes of this study were to examine the role of transcription factor EB (TFEB) in regulating TAM gene expression and function and to determine if TFEB activation can halt breast tumor development.

Methods

Microarrays were used to analyze the gene expression profile of macrophages (MΦs) in the context of breast cancer and to examine the impact of TFEB overexpression. Cell culture studies were performed to define the mechanisms by which TFEB affects MΦ gene expression and function. Mouse studies were carried out to investigate the impact of MΦ TFEB deficiency or activation on breast tumor growth. Human cancer genome data were analyzed to reveal the prognostic value of TFEB and its regulated genes.

Results

TAM-mimic MΦs display a unique gene expression profile, including significant reduction in TFEB expression. TFEB overexpression favorably modulates TAM gene expression through multiple signaling pathways. Specifically, TFEB upregulates suppressor of cytokine signaling 3 (SOCS3) and peroxisome proliferator-activated receptor γ (PPARγ) expression and autophagy/lysosome activities, inhibits NLRP3 (NLR Family Pyrin Domain Containing 3) inflammasome and hypoxia-inducible factor (HIF)-1α mediated hypoxia response, and thereby suppresses an array of effector molecules in TAMs including arginase 1, interleukin (IL)-10, IL-1β, IL-6 and prostaglandin E2. MΦ-specific TFEB deficiency promotes, while activation of TFEB using the natural disaccharide trehalose halts, breast tumor development by modulating TAMs. Analysis of human patient genome database reveals that expression levels of TFEB, SOCS3 and PPARγ are positive prognostic markers, while HIF-1α is a negative prognostic marker of breast cancer.

Conclusions

Our study identifies TFEB as a master regulator of TAMs in breast cancer. TFEB controls TAM gene expression and function through multiple autophagy/lysosome-dependent and independent pathways. Therefore, pharmacological activation of TFEB would be a promising therapeutic approach to improve the efficacy of existing treatment including immune therapies for breast cancer by favorably modulating TAM function and the TME.
Invertebrate colonization of a newly constructed diversion channel in the Canadian Shield
Authors: Chapelsky Andrew J. , Guzzo Matthew M. , Hrenchuk Lee E. , Blanchfield Paul J.
Published: June 2020

Construction of artificial channels to divert water is common in a variety of natural resource development projects; however, the length of time required for these stream channels to become productive fish habitat remains an understudied aspect. The creation of a bedrock channel (∼150 m) to drain a third-order boreal lake and its watershed (∼300 ha) offered the unique opportunity to study colonization by comparing habitat and invertebrate metrics with a reference stream. The amount of riparian vegetation on the banks of the diversion channel steadily increased, but remained much lower than the reference stream after 5 years. The channel was quickly colonized by benthic macroinvertebrates, which were of comparable abundance to the reference stream starting in the first year, and thereafter were greater in abundance. Taxa diversity and richness responded more slowly, becoming similar to the reference stream after 3 years. Results from this study suggest that newly created, lake-outlet channels can become productive small stream habitats in a relatively short time period (<5 years) in southern boreal regions.
TeV scale leptogenesis via dark sector scatterings
Authors: Borah Debasish , Dasgupta Arnab , Kang Sin Kyu
Published: June 2020

We propose a novel scenario of generating lepton asymmetry via annihilation and coannihilation of dark sector particles including t-channel processes. In order to realistically implement this idea, we consider the scotogenic model having three right handed neutrinos and a new scalar doublet, all of which are odd under an in-built $$Z_2$$Z2 symmetry. The lightest $$Z_2$$Z2 odd particle, if electromagnetically neutral, can be a dark matter candidate while annihilation and coannihilation between different $$Z_2$$Z2 odd particles into standard model leptons serve as the source of lepton asymmetry. The light neutrino masses arise at one loop level with $$Z_2$$Z2 odd fields going inside the loop. We show that experimental data related to light neutrinos, dark matter relic abundance and baryon asymmetry can be simultaneously satisfied in the model for two different cases: one with fermion dark matter and the other with scalar dark matter. In both scenarios, t-channel annihilation as well as coannihilation of $$Z_2$$Z2 odd particles play a non-trivial role in producing the non-zero CP asymmetry. Both the scenarios remain allowed from DM direct detection while keeping the scale of leptogenesis as low as TeV or less, lower than the one for vanilla leptogenesis scenario in scotogenic model along with the additional advantage of explaining the baryon-dark matter coincidence to some extent. Due to such low scale, the model is testable through rare decay experiments looking for charged lepton flavour violation.
ABCNet: an attention-based method for particle tagging
Authors: Mikuni V. , Canelli F.
Published: June 2020

In high energy physics, graph-based implementations have the advantage of treating the input data sets in a similar way as they are collected by collider experiments. To expand on this concept, we propose a graph neural network enhanced by attention mechanisms called ABCNet. To exemplify the advantages and flexibility of treating collider data as a point cloud, two physically motivated problems are investigated: quark–gluon discrimination and pileup reduction. The former is an event-by-event classification, while the latter requires each reconstructed particle to receive a classification score. For both tasks, ABCNet shows an improved performance compared to other algorithms available.
Topological characterization of C2 via open algebraic surface theory
Authors: Gurjar R. V. , Gurjar Sudarshan
Published: June 2020

We will give a new proof of Ramanujam’s topological characterization of the affine [Formula: see text]-space [Formula: see text] using the Abhyankar–Moh–Suzuki theorem on embeddings of the affine line in [Formula: see text] and some ideas from the theory of open algebraic surfaces.
CAUSALITY BETWEEN PEER-TO-PEER LENDING AND BANK LENDING IN CHINA: EVIDENCE FROM A PANEL DATA APPROACH
Authors: WU TSUNG-PAO , WU HUNG-CHE , LIU SHU-BING , HSUEH HSIN-PEI , WANG CHIEN-MING
Published: June 2020

This study applied a multivariate panel Granger causality test to examine the causal relationship between peer-to-peer lending (P2PL) and bank lending (BL) in China’s eight major regions for the period from 2014M01 to 2019M12. The empirical results of this paper support evidence for the P2PL leading hypothesis in regions such as Jiangsu and Hubei while the BL leading hypothesis relationship supports the evidence for regions such as Zhejiang and Shanghai. In addition, there is an interactive causal relationship between P2PL and BL in a region such as Shandong. However, the result of a neutrality hypothesis supports three of these eight major regions (Guangdong, Beijing and Sichuan). The findings of this paper provide important policy implications for China’s eight major regions as well as business sectors in the banking industry for understanding and predicting market conditions.
The curvature effect on the gravitational collapse of interacting and non-interacting combination of dark matter and dark energy
Authors: Abbas S. Z. , Shah H. H. , Chammam W. , Sun H. , Ul Haq Wasim , Shah H.
Published: June 2020

The study of gravitational collapse is a very interesting phenomena in general relativistic astrophysics. Here, in this study we investigated the gravitational collapse of a spherically symmetric core of a star, constituted of dark matter (DM) ([Formula: see text]), in dark energy (DE) ([Formula: see text]) background. It was investigated that gravitational collapse of interacting and noninteracting combination of DM and DE yields BH formation. In this work, our main aim is to examine the effect of space–time curvature [Formula: see text] on the gravitational collapse of interacting and noninteracting combination of dark matter and DE. We achieve the visible influence of curvature on gravitational collapse analytically and interpret the results graphically.
The atmospheric turbulence characteristics in a diurnal cycle
Authors: Song Yi-Lei , Tian Lin-Lin , Zhao Ning
Published: June 2020

During a whole-day period, profiles of mean wind speed, wind shear and turbulence level shows great variability due to continuously varying atmospheric stability. Clearly understanding the spatial and temporal behaviors of the atmospheric wind flow is of great importance for science purposes. Large-eddy simulation (LES) technique is employed here to reproduce the evolution of atmospheric flow during a diurnal cycle. With the obtained LES results, wind characteristics in terms of wind speed, wind shear, turbulence intensity and turbulent kinetic energy can be examined referring to the stability classification. Besides, wind profiles obtained using currently available engineering models are also included for comparison. Disparities between the model predictions and the LES results illustrate that the standard engineering models cannot well capture the wind characteristics driven by the varying atmospheric stability solely, and a further improvement in models is highly needed.
Effect of mach number on high-subsonic and low-Reynolds-number flows around airfoils
Authors: Xu Jian-Hua , Song Wen-Ping , Han Zhong-Hua , Zhao Zi-Hao
Published: June 2020

High-subsonic and low-Reynolds-number flow is a special aerodynamic problem associated with near space propellers and Mars aircrafts. The flow around airfoils and the corresponding aerodynamic performance are different from the incompressible flow at low-Reynolds-number, due to complex shock wave-laminar separation bubble interaction. The objective of this paper is to figure out the effect of Mach number on aerodynamic performance and special flow structure of airfoil. An in-house Reynolds-averaged Navier–Stokes solver coupled with [Formula: see text] transition model is employed to simulate the flows around the E387 airfoil. The results show that the lift slope is larger than [Formula: see text] in the linear region. No stall occurs even at an attack angle of [Formula: see text]. With increase of Mach number, lift coefficient decreases when attack angle is below [Formula: see text]. However, once the angle of attack exceeds [Formula: see text], higher Mach number corresponds to higher lift coefficient. In addition, the strength and number of shock waves are very sensitive to Mach number. With increase of Mach number, the region of reverse flow vortex near transition location becomes smaller and finally disappears, while a new reverse flow vortex appears near the trailing edge and becomes larger.
Stochastic analysis of a nonlinear electromagnetic energy harvesting system with fractional damping under additive and multiplicative stochastic excitation
Authors: Ma Du-Meng , Zhang Shu-Ling , Zhang Ying , Xu Wei
Published: June 2020

Electromagnetic energy harvester has been widely concerned in recent years due to its advantages of small size and high sensing frequency. In this paper, the stochastic behaviors of a nonlinear electromagnetic energy harvesting system (NEEH) with fractional damping are investigated under the additive and multiplicative stochastic excitation. Firstly, by applying the stochastic average method to the NEEH system, the mean square of the output current, and the steady-state probability density of vibration amplitude, displacement and velocity are obtained. Meanwhile, the validity of the theoretical results is verified by comparing with the numerical results given by the Monte Carlo method. Secondly, by investigating the theoretical and numerical results, the influences of noise intensity and fractional order on the NEEH system are explored. It is obvious that a higher output voltage can be obtained by the larger intensity of the stochastic excitation, and the smaller coefficient and fractional order of the fractional damping.
On the exact and numerical solutions to the FitzHugh–Nagumo equation
Authors: Yokus Asıf
Published: June 2020

In this paper, with the help of a computer package program, the auto-Bäcklund transformation method (aBTM) and the finite forward difference method are used for obtaining the wave solutions and the numeric and exact approximations to the FitzHugh–Nagumo (F-N) equation, respectively. We successfully obtain some wave solutions to this equation by using aBTM. We then employ the finite difference method (FDM) in approximating the exact and numerical solutions to this equation by taking one of the obtained wave solutions into consideration. We also present the comparison between exact and numeric approximations and support the comparison with a graphic plot. Moreover, the Fourier von-Neumann stability analysis is used in checking the stability of the numeric scheme. We also present the [Formula: see text] and [Formula: see text] error norms of the solutions to this equation.
Investigation on low-frequency broadband characteristics of three-dimensional acoustic black hole superstructures
Authors: Zhou Zhuo , Liang Xiao , Wu Jiu Hui , Shang Peng , Niu Jiamin
Published: June 2020

In order to solve the problem of strong penetration and difficult attenuation of low-frequency sound wave in traditional materials, several three-dimensional acoustic black hole superstructures are designed. First of all, multi-stage acoustic black holes are designed. It is found that their sound insulation coefficient is about 0.9 in the frequency range of 50–1600 Hz when the ration of the outlet tip diameter to the inlet diameter is [Formula: see text]. Then, the acoustic black hole thin and light superstructure was designed by embedding many acoustic black hole units in an array on the 10 mm thick plate. The sound insulation coefficient of two samples embedded 81 or 144 acoustic black holes is above 0.96 in the frequency range of 50–1600 Hz. To facilitate processing and engineering applications, we designed acoustic black hole wedge-shaped plate superstructures, and found that the average sound insulation of these acoustic black hole superstructures is 30 dB in the frequency range of 50–1600 Hz. These superstructures will be widely used in anechoic rooms, factories and aviation.
Control and synchronization in nonlinear circuits by using a thermistor
Authors: Zhang Xiufang , Wang Chunni , Ma Jun , Ren Guodong
Published: June 2020

The survival and occurrence of chaos are much dependent on the intrinsic nonlinearity and parameters region for deterministic nonlinear systems, which are often represented by ordinary differential equations and maps. When nonlinear circuits are mapped into dimensional dynamical systems for further nonlinear analysis, the physical parameters of electric components, e.g. capacitor, inductor, resistance, memristor, can also be replaced by dynamical parameters for possible adjustment. Slight change for some bifurcation parameters can induce distinct mode transition and dynamics change in the chaotic systems only when the parameter is adjustable and controllable. In this paper, a thermistor is included into the chaotic Chua circuit and the temperature effect is considered by investigating the mode transition in oscillation and the dependence of Hamilton energy on parameters setting in thermistor. Furthermore, the temperature of thermistor is adjusted for finding possible synchronization between two chaotic Chua circuits connected by a thermistor. When the coupling channel via thermistor connection is activated, two identical Chua circuits (periodical or chaotic oscillation) can reach complete synchronization. In particular, two periodical Chua circuits can be coupled to present chaotic synchronization by taming parameters in thermistor of coupling channel. However, phase synchronization is reached while complete synchronization becomes difficult when the coupling channel is activated to coupling a periodical Chua circuit and a chaotic Chua circuit. It can give guidance for further control of firing behaviors in neural circuits when the thermistor can capture the heat effectively.
Analytical methods: Nonlinear longitudinal wave equation in a magnetoelectro-elastic circular rod, foam drainage and modified Degasperis–Procesi models arising in nonlinear water wave models
Authors: Seadawy Aly , Ali Asghar , Jhangeer Adil
Published: June 2020

We form the analytical solitary wave solutions with the execution of generalized direct algebraic technique on three well-known nonlinear wave models, namely, called foam drainage, longitudinal magnetoelectro-elastic circular rod and modified Degasperis–Procesi equations. The derived solutions are hyperbolic functions in which some are plotted graphically on meticulous values to the parameters which provides the basic knowledge to understand physical significant of these three wave models. The obtained solutions show the efficiency and precision of our scheme. These derived new results prove that our novel technique is awfully effective and can be productive as a instrument solving for sundry other nonlinear evolution equations.
LASER SURFACE REINFORCEMENT OF THE Ti/Al TIG WELDED JOINT
Authors: YE ZHIYUN , LI JIANING , WANG JUAN , XU SHUBO , JING CAINIAN , ZHAO YANHUA , LI GUANCHAO , GAN XINZHU , MA FUKUN , YU FUSHENG
Published: June 2020

The microstructure of the Ti/Al weld seam (WS) was uniform, and a good metallurgy bond between TC4/5052 aluminum alloy substrates was obtained without obvious defects after the Tungsten inert gas (TIG) process. Then, a remelt layer (RL) with fine microstructure can be formed by means of a laser remelting (LR) technique of the Ti/Al TIG joints. The Ti–Al intermetallics were produced adhered to the weld joints’ surface, exhibiting the extreme high surface hardness. The micro-hardness distribution of this RL surface was in a range of 1150–1200 HV[Formula: see text], which was significantly higher than that of the TC4 titanium alloy substrate. The high micro-hardness of the weld joints’ surface can be mainly ascribed to the actions of the Ti–Al intermetallics, the fine grain and the solid solution strengthening.
Affine connections of non-integrable distributions
Authors: Wang Yong
Published: June 2020

In this paper, we study non-integrable distributions in a Riemannian manifold with a semi-symmetric metric connection, a kind of semi-symmetric non-metric connection and a statistical connection. We obtain the Gauss, Codazzi, and Ricci equations for non-integrable distributions with respect to the semi-symmetric metric connection, the semi-symmetric non-metric connection and the statistical connection. As applications, we obtain Chen’s inequalities for non-integrable distributions of real space forms endowed with a semi-symmetric metric connection and a kind of semi-symmetric non-metric connection. We give some examples of non-integrable distributions in a Riemannian manifold with affine connections. We find some new examples of Einstein distributions and distributions with constant scalar curvature.
Spectral method of analysis and optimal estimation in linear stochastic systems
Authors: Rybakov K. A.
Published: June 2020

It is proposed to use the spectral form of mathematical description of control systems for modeling continuous-time Markov random processes described by linear stochastic differential equations with additive or multiplicative noise. The obtained results are applied to solve the output process analysis problem and the optimal estimation problem.
Processing Grid-format Real-world Graphs on DRAM-based FPGA Accelerators with Application-specific Caching Mechanisms
Authors: Shao Zhiyuan , Liu Chenhao , Li Ruoshi , Liao Xiaofei , Jin Hai
Published: June 2020

Graph processing is one of the important research topics in the big-data era. To build a general framework for graph processing by using a DRAM-based FPGA board with deep memory hierarchy, one of the reasonable methods is to partition a given big graph into multiple small subgraphs, represent the graph with a two-dimensional grid, and then process the subgraphs one after another to divide and conquer the whole problem. Such a method (grid-graph processing) stores the graph data in the off-chip memory devices (e.g., on-board or host DRAM) that have large storage capacities but relatively small bandwidths, and processes individual small subgraphs one after another by using the on-chip memory devices (e.g., FFs, BRAM, and URAM) that have small storage capacities but superior random access performances. However, directly exchanging graph (vertex and edge) data between the processing units in FPGA chip with slow off-chip DRAMs during grid-graph processing leads to limited performances and excessive data transmission amounts between the FPGA chip and off-chip memory devices.

In this article, we show that it is effective in improving the performance of grid-graph processing on DRAM-based FPGA hardware accelerators by leveraging the flexibility and programmability of FPGAs to build application-specific caching mechanisms, which bridge the performance gaps between on-chip and off-chip memory devices, and reduce the data transmission amounts by exploiting the localities on data accessing. We design two application-specific caching mechanisms (i.e.,
vertex caching
and
edge caching
) to exploit two types of localities (i.e.,
vertex locality
and
subgraph locality
) that exist in grid-graph processing, respectively. Experimental results show that with the vertex caching mechanism, our system (named as FabGraph) achieves up to 3.1× and 2.5× speedups for BFS and PageRank, respectively, over ForeGraph when processing medium graphs stored in the on-board DRAM. With the edge caching mechanism, the extension of FabGraph (named as FabGraph+) achieves up to 9.96× speedups for BFS over FPGP when processing large graphs stored in the host DRAM.
FPGA Logic Block Architectures for Efficient Deep Learning Inference
Authors: Eldafrawy Mohamed , Boutros Andrew , Yazdanshenas Sadegh , Betz Vaughn
Published: June 2020

Reducing the precision of deep neural network (DNN) inference accelerators can yield large efficiency gains with little or no accuracy degradation compared to half or single precision floating-point by enabling more multiplication operations per unit area. A wide range of precisions fall on the pareto-optimal curve of hardware efficiency vs. accuracy with no single precision dominating, making the variable precision capabilities of FPGAs very valuable. We propose three types of logic block architectural enhancements and fully evaluate a total of six architectures that improve the area efficiency of multiplications and additions implemented in the soft fabric. Increasing the LUT fracturability and adding two adders to the ALM (4-bit Adder Double Chain architecture) leads to a 1.5× area reduction for arithmetic heavy machine learning (ML) kernels, while increasing their speed. In addition, this architecture also reduces the logic area of general applications by 6%, while increasing the critical path delay by only 1%. However, our highest impact option, which adds a 9-bit shadow multiplier to the logic clusters, reduces the area and critical path delay of ML kernels by 2.4× and 1.2×, respectively. These large gains come at a cost of 15% logic area increase for general applications.
A Correlative Study of Polyaniline Electropolymerization and its Electrochromic Behavior
Authors: Korent Anja , Žagar Soderžnik Kristina , Šturm Sašo , Žužek Rožman Kristina
Published: June 2020

The electrochemical polymerization of polyaniline (PANI) was studied using correlative measurements of electrochemistry and UV–vis spectroscopy, i.e., spectroelectrochemistry. The electropolymerization of PANI was performed in an acidic medium (1 M HCl) containing 0.1 M aniline with cyclic voltammetry (CV) in a potential window from −0.3 to 1 V and a 50 mV s−1scan rate. At the same time, UV–vis absorbance spectra in the wavelength range from 200 to 900 nm were measured for every 10 mV change in the CV. The CV results show the oxidation of the monomer at a high positive potential (0.9 V vs Ag), the continuous growth of the PANI film and the transformation between the three best-known forms of PANI redox in the potential range between −0.3 V and 1 V. In parallel, the spectroscopic study confirmed the formation of PANI oxidation. The spectroscopic results showed the formation of the final conductive PANI product (emeraldine salt) due to the absorbance of the formed charge carriers (polarons, bipolarons) during the polymerization. The correlative electrochemical/spectroscopy study gave an additional dimension to the PANI polymerization mechanism, where not only was the oxidation the lead type of reaction, but the reduction was also found to play an important role.
Eye and head movements and vestibulo-ocular reflex in the context of indirect, referent control of motor actions
Authors: Feldman Anatol G. , Zhang Lei
Published: June 2020

Conventional explanations of the vestibulo-ocular reflex (VOR) and eye and head movements are revisited by considering two alternative frameworks addressing the question of how the brain controls motor actions. Traditionally, biomechanical and/or computational frameworks reflect the views of several prominent scholars of the past, including Helmholtz and von Holst, who assumed that the brain directly specifies the desired motor outcome and uses efference copy to influence perception. However, empirical studies resulting in the theory of referent control of action and perception (an extension of the equilibrium-point hypothesis) revealed that direct specification of motor outcome is inconsistent with nonlinear properties of motoneurons and with the physical principle that the brain can control motor actions only indirectly, by changing or maintaining the values of neurophysiological parameters that influence, but can remain independent of, biomechanical variables. Some parameters are used to shift the origin (referent) points of spatial frames of reference (FRs) or system of coordinates in which motor actions emerge without being predetermined. Parameters are adjusted until the emergent motor actions meet the task demands. Several physiological parameters and spatial FRs have been identified, supporting the notion of indirect, referent control of movements. Instead of integration of velocity-dependent signals, position-dimensional referent signals underlying head motion can likely be transmitted to motoneurons of extraocular muscles. This would produce compensatory eye movement preventing shifts in gaze during head rotation, even after bilateral destruction of the labyrinths. The referent control framework symbolizes a shift in the paradigm for the understanding of VOR and eye and head movement production.
Gut Microbiota in Liver Disease: What Do We Know and What Do We Not Know?
Authors: Jiang Lu , Schnabl Bernd
Published: June 2020

The gut and the liver have a bidirectional communication via the biliary system and the portal vein. The intestinal microbiota and microbial products play an important role for modulating liver diseases such as alcohol-associated liver disease, non-alcoholic fatty liver disease and steatohepatitis, and cholestatic liver diseases. Here, we review the role of the gut microbiota and its products for the pathogenesis and therapy of chronic liver diseases.
Essential Role of Hemoglobin βCys93 in Cardiovascular Physiology
Authors: Premont Richard T. , Stamler Jonathan S.
Published: June 2020

The supply of oxygen to tissues is controlled by microcirculatory blood flow. One of the more surprising discoveries in cardiovascular physiology is the critical dependence of microcirculatory blood flow on a single conserved cysteine within the β-subunit (βCys93) of hemoglobin (Hb). βCys93 is the primary site of Hb S-nitrosylation [i.e., S-nitrosothiol (SNO) formation to produce S-nitrosohemoglobin (SNO-Hb)]. Notably, S-nitrosylation of βCys93 by NO is favored in the oxygenated conformation of Hb, and deoxygenated Hb releases SNO from βCys93. Since SNOs are vasodilatory, this mechanism provides a physiological basis for how tissue hypoxia increases microcirculatory blood flow (hypoxic autoregulation of blood flow). Mice expressing βCys93A mutant Hb (C93A) have been applied to understand the role of βCys93, and RBCs more generally, in cardiovascular physiology. Notably, C93A mice are unable to effect hypoxic autoregulation of blood flow and exhibit widespread tissue hypoxia. Moreover, reactive hyperemia (augmentation of blood flow following transient ischemia) is markedly impaired. C93A mice display multiple compensations to preserve RBC vasodilation and overcome tissue hypoxia, including shifting SNOs to other thiols on adult and fetal Hbs and elsewhere in RBCs, and growing new blood vessels. However, compensatory vasodilation in C93A mice is uncoupled from hypoxic control, both peripherally (e.g., predisposing to ischemic injury) and centrally (e.g., impairing hypoxic drive to breathe). Altogether, physiological studies utilizing C93A mice are confirming the allosterically controlled role of SNO-Hb in microvascular blood flow, uncovering essential roles for RBC-mediated vasodilation in cardiovascular physiology and revealing new roles for RBCs in cardiovascular disease.
Prediction and Analysis of the Aerodynamic Characteristics of a Spinning Projectile Based on Computational Fluid Dynamics
Authors: Ko Arim , Chang Kyoungsik , Sheen Dong-Jin , Lee Chi-Hoon , Park Yongin , Park Sung Woo
Published: June 2020

Numerical simulations of a spinning projectile with a diameter of 120 mm were conducted to predict the aerodynamic coefficients, and the CFD results were compared with the semiempirical method, PRODAS. Six coefficients or coefficient derivatives, including zero and the quadratic drag coefficient, lift force coefficient derivative, Magnus force coefficient derivative, overturning moment coefficient, and spinning damping moment coefficient, which are important parameters for solving the equations of motion of the spinning projectile, were investigated. Additionally, the nonlinear behavior of these coefficients and coefficient derivatives were analyzed through the predicted flow fields. The considered Mach number ranges from 0.14 to 1.2, and the nondimensional spinning rate (PD/2V) is set to 0.186. To calculate the coefficient derivative of the corresponding force or moment, additional simulations were conducted at the angle of attack of 2.5 degrees. The simulation results were able to predict nonlinear behavior, the especially abrupt change of the predicted coefficients and derivatives at the transonic Mach number, 0.95. The simulation results, including the skin friction, pressure, and velocity field, allow the characterization of the nonlinear behavior of the aerodynamic coefficients, thus, enabling better predictions of projectile trajectories.
Interplay between Oxidative Stress, Inflammation, and Amyloidosis in the Anterior Segment of the Eye; Its Pathological Implications
Authors: Perez-Garmendia Roxanna , Lopez de Eguileta Rodriguez Alicia , Ramos-Martinez Ivan , Zuñiga Nayeli Martínez , Gonzalez-Salinas Roberto , Quiroz-Mercado Hugo , Zenteno Edgar , Hernández Eleazar Ramírez , Hernández-Zimbrón Luis Fernando
Published: June 2020

There are different pathologies associated with amyloidogenic processes caused by the increase of reactive oxygen species (ROS) and the overactivation of inflammatory responses. These alterations are present in different regions of the anterior segment of the eye, and they have been associated with the development and progression of ocular pathologies, such as glaucoma, dry eye syndrome, keratitis, and cataracts among other pathologies. Aim. To discuss briefly the anatomical characteristics of the anterior segment of the eye and describe the interaction between oxidative stress (OS) and inflammatory responses, emphasizing the misfolding of several proteins leading to amyloidogenic processes occurring in the anterior segment and their implications in the development of ocular diseases. We performed a search on PubMed, CINAHL, and Embase using the MeSH terms “eye,” “anterior segment”, “inflammation”, “oxidative stress”, and “amyloidosis”. The search encompassed manuscripts published up to April 2019. A hundred forty-four published studies met the inclusion criteria. We present the current knowledge regarding the interaction between OS and the activation of inflammatory processes and how both can cause conformational changes in several peptides and proteins in each compartment of the anterior segment. However, we found that there is no consensus about which factor is the first to cause amyloidosis. Our conclusions suggest that there is an interplay among these factors forming a vicious cycle that leads to the loss of protein structure in ocular pathologies, and multifactorial therapies should be developed to avoid protein misfolding and to stop the progression of ocular pathologies.
Enhanced Efficacy of Direct-Acting Antivirals in Hepatitis C Patients by Coadministration of Black Cumin and Ascorbate as Antioxidant Adjuvants
Authors: Ahmed Sarfraz , Zahoor Adeela , Ibrahim Muhammad , Younus Muhammad , Nawaz Sadia , Naseer Rahat , Akram Qaiser , Deng Cun-Liang , Ojha Suvash Chandra
Published: June 2020

The widespread adaptation of a new generation of direct-acting antiviral agents (DAAs) unveils a superlative effect in the eradication of the hepatitis C virus (HCV). However, this therapy has been reported to exhibit vigorous side effects that pose a risk in fleet recovery. This study was conducted to investigate the efficacy of DAAs: sofosbuvir (SOF) and ribavirin (RBV), along with black cumin (BLC) and ascorbate (ASC), as adjuvants on hematological parameters; oxidative stress markers such as total antioxidant status (TAS), superoxide dismutase (SOD), reduced (GSH) and oxidized (GSSG) glutathione (GSH), gamma-glutamyl transferase (GGT), and malondialdehyde (MDA); liver function markers such as aspartate transaminase (AST), alanine aminotransferase (ALT), bilirubin, and alkaline phosphatase (ALP); and viral load with determined genotypes. HCV-infected patients (n=30) were randomly divided into two equal groups: control group (n=15) and treatment group (n=15). The control group was subjected only to SOF and RBV (400 mg each/day). Synergistically, the treatment group was administered with adjuvant therapy of BLC (250 mg/day) and ASC (1000 mg/day) along with DAAs (400 mg each/day) for 8 weeks. All selected patients were subjected to sampling at pre- and posttreatment stages for the assessment of defined parameters. The data revealed that the BLC/ASC adjuvant therapy boosted the efficacy of DAAs by reducing the elevated levels of liver markers such as AST, ALT, ALP, and bilirubin in the treatment group compared with those in the control group (P>0.05). The adjuvant therapy synchronously showed an ameliorating effect on hematological parameters. The SOF/RBV with adjuvant therapy also demonstrated an increasing effect in the activity of SOD, TAS, and GSH and a decreasing effect for GSSG, GGT, and malondialdehyde (MDA;P>0.05) followed by curtailing a RT-PCR-quantified viral load. Our findings provide evidence that systemic administration of BLC/ASC efficiently alleviates hematological, serological, and antioxidant markers as well as the viral load in hepatitis C patients. This highlights a potentially novel role of BLC and ASC in palliating hepatitis C.
CKF-Based Visual Inertial Odometry for Long-Term Trajectory Operations
Authors: Nguyen Trung , Mann George K. I. , Vardy Andrew , Gosine Raymond G.
Published: June 2020

The estimation error accumulation in the conventional visual inertial odometry (VIO) generally forbids accurate long-term operations. Some advanced techniques such as global pose graph optimization and loop closure demand relatively high computation and processing time to execute the optimization procedure for the entire trajectory and may not be feasible to be implemented in a low-cost robotic platform. In an attempt to allow the VIO to operate for a longer duration without either using or generating a map, this paper develops iterated cubature Kalman filter for VIO application that performs multiple corrections on a single measurement to optimize the current filter state and covariance during the measurement update. The optimization process is terminated using the maximum likelihood estimate based criteria. For comparison, this paper also develops a second solution to integrate VIO estimation with ranging measurements. The wireless communications between the vehicle and multiple beacons produce the ranging measurements and help to bound the accumulative errors. Experiments utilize publicly available dataset for validation, and a rigorous comparison between the two solutions is presented to determine the application scenario of each solution.