bluuebunny/crossref_metadata_2025 huggingface dataset:
Two braincases of Daspletosaurus (Theropoda: Tyrannosauridae): anatomy and comparison1
Authors: Paulina Carabajal Ariana , Currie Philip J. , Dudgeon Thomas W. , Larsson Hans C.E. , Miyashita Tetsuto
Published: August 2021

For sheer complexity, braincases are generally considered anatomically conservative. However, recent research on the braincases of tyrannosaurids have revealed extensive morphological variations. This line of inquiry has its root in Dale Russell’s review of tyrannosaurids in which he established Daspletosaurus torosus — a large tyrannosaurine from the Campanian of southern Alberta. In the wake of systematic revisions to tyrannosaurines previously assigned to Daspletosaurus, one potentially distinct species remains undescribed. This paper describes and compares a braincase referable to this species with that of the holotype for Daspletosaurus torosus using computerized-tomography-based reconstructions. The two braincases have numerous differences externally and internally. The specimen of Daspletosaurus sp. has a bottlenecked olfactory tract, short and vertical lagena, and a developed ascending column of the anterior tympanic recess. The holotype of Daspletosaurus torosus has many unusual traits, including an anteriorly positioned trochlear root, elongate common carotid canal, distinct chamber of the basisphenoid recess, asymmetry in the internal basipterygoid aperture, and laterally reduced but medially expanded subcondylar recess. This comparison also identified characters that potentially unite the two species of Daspletosaurus, including deep midbrain flexures in the endocasts. However, many character variations in the braincases are known in other tyrannosaurids to correlate with body size and maturity, or represent individual variations. Therefore, taxonomic and phylogenetic signals can be isolated from background variations in a more comprehensive approach by using additional specimens. New information on the two braincases of Daspletosaurus is consistent with the emerging view of tyrannosaurid braincases as highly variable, ontogenetically dynamic character complexes.
Mechanism of acitretin-induced relaxations in isolated rat thoracic aorta preparations
Authors: Efe Oğuzhan Ekin , Aydos Tolga Reşat , Emre Aydingoz Selda
Published: August 2021

Acitretin is a member of vitamin A-derived retinoids, and its effect on vascular smooth muscle had not yet been studied. The aim of this study is to investigate the effect of acitretin, a retinoid, on vascular smooth muscle contractility. Thoracic aorta preparations obtained from 34 male Sprague–Dawley rats (355 ± 15 g) were studied in isolated organ baths containing Krebs–Henseleit solution. The relaxation responses were obtained with acitretin (10–12–10–4 M) in endothelium-preserved and endothelium-denuded aorta preparations precontracted with submaximal concentration of phenylephrine (10–6 M). The role of retinoic acid receptors (RARs), nitric oxide, adenylyl, and guanylyl cyclase enzymes, and potassium channels in these relaxation responses were investigated. Acitretin produced concentration-dependent relaxations, which were independent of its solvent dimethylsulfoxide (DMSO), in endothelium-denuded phenylephrine-precontracted thoracic aorta preparations. While incubation with the RAR antagonist (AGN193109, 10–5 M) had no effect on these relaxations; nitric oxide synthase inhibitor (L-NG-Nitro arginine methyl ester (L-NAME), 10–4 M), adenylyl cyclase inhibitor (SQ2253, 10–5 M), guanylyl cyclase inhibitor (oxadiazolo [4,3-a] quinoxalin-1-one (ODQ), 10–6 M), and potassium channel blocker (tetraethylammonium (TEA), 10–2 M) significantly eliminated the relaxation responses induced by acitretin. Acitretin induces relaxation in rat isolated thoracic aorta preparations without endothelium, which may be mediated by nitric oxide, cyclic adenosine monophosphate, and cyclic guanosine monophosphate-dependent kinases and potassium channels.
Substructure Damage Identification Based on Model Updating of Frequency Response Function
Authors: Fang Youliang , Su Pengrui , Shao Jingyu , Lou Jiaqi , Zhang Ying
Published: August 2021

Model updating of large-scale structures is difficult to carry out when using a frequency response function (FRF) for damage identification, as the solutions for the global system matrices with too many degrees of freedom are required in each iteration. In this paper, a substructure damage identification method is proposed based on the model updating of the acceleration FRF. The original finite element model is divided into several substructures using the improved reduced system (IRS) by the dynamic condensation method, resulting in the simplified substructure model. The final simplified model is composed of the simplified mass matrix and stiffness matrix of the substructure considered. The damage acceleration FRF to be identified is used to iteratively update the simplified model. The locations and extents of the damage elements are obtained by updating the results, which reduces the number of uncertain parameters to be updated and leads to the rapid convergence of the optimization process. In the iteration, L1 norm regularization is introduced to solve the ill-posed problem, which improves the stability of the identification results. A numerical simulation of a six-story steel frame structure under various working conditions was carried out to verify the effectiveness of the proposed method, which was also validated by the experiments. The robustness and performance of the proposed damage identification method based on substructures have been demonstrated.
Benefits on Sales Generated by Innovation
Authors: Taques Fernando Henrique , Areal Nelson , Basso Leonardo Fernando Cruz
Published: August 2021

The object of the research is to assess whether organizations’ ability to innovate may be able to explain abnormal returns to firms by composing risk factor models. Using R&D investment indicators and published patents from a global sample of companies for the period 1992 to 2018, the 3-factor, 4-factor and 5-factor risk models were applied. Partly the case is that increased investment in innovation contributes to better sales performance and, consequently, excess returns. Regarding the rolling-regression method, the results show few scenarios in which the ability to innovate is an explanatory factor for financial performance.
Hamiltonian trace graph of matrices
Authors: Sivagami M. , Tamizh Chelvam T.
Published: August 2021

Let [Formula: see text] be a commutative ring with identity, [Formula: see text] be a positive integer and [Formula: see text] be the set of all [Formula: see text] matrices over [Formula: see text] For a matrix [Formula: see text] Tr[Formula: see text] is the trace of [Formula: see text] The trace graph of the matrix ring [Formula: see text] denoted by [Formula: see text] is the simple undirected graph with vertex set [Formula: see text][Formula: see text] and two distinct vertices [Formula: see text] and [Formula: see text] are adjacent if and only if Tr[Formula: see text] The ideal-based trace graph of the matrix ring [Formula: see text] with respect to an ideal [Formula: see text] of [Formula: see text] denoted by [Formula: see text] is the simple undirected graph with vertex set [Formula: see text] and two distinct vertices [Formula: see text] and [Formula: see text] are adjacent if and only if Tr[Formula: see text] In this paper, we investigate some properties and structure of [Formula: see text] Further, it is proved that both [Formula: see text] and [Formula: see text] are Hamiltonian.
Enumeration of n-hypergroups on sets with two elements
Authors: Safari M. B. , Davvaz B.
Published: August 2021

This paper is a continuation of ideas presented in [M. B. Safari, B. Davvaz and V. Leoreanu-Fotea, Enumeration of 3- and 4-hypergroups on sets with two elements, Eur. J. Combin. 44 (2015) 298–306]. We find the number and structure of non-isomorphism [Formula: see text]-hypergroups on sets with two elements. Moreover, we present a general template for some special cases of [Formula: see text]-hypergroups by linking the last results on [Formula: see text]-hypergroups.
The Role of Nanotechnology in Antiviral Regime: An Overview
Authors: Singh Reena , Gupta Seema , Kumar Pradeep
Published: August 2021

Nanomedicine or nanotechnology exhibits outstanding features to challenge severe health issues including pathogenic viral infections, the most culpable invaders in the present situation. The perpetual mutational pattern in viruses topped with raising resistance to drug epitomizes the current situation as a trigger to explore nanotech platforms in antiviral therapies. Referring to novel physicochemical features of nanomaterials associated with effective drug delivery, it is viewed as an ideal strategy for treatment of viral infections. The coronavirus induced pathogenesis, including MERS, SARS and SARS-CoV-2 infections, has triggered alarming and highly dangerous precedents against existence of humans. Applications of nanotechnology can serve a new direction for disinfection or treatment of viruses. Presently, various types of nanomaterials, such as nanogels, nanospheres, nanocapsules, liposomes, nanoparticles and many others, that have been investigated in vivo and in vitro for successful drug delivery, vaccination, diagnostic assay and device development with anticipation to be translated in advanced clinical practices, need a collective relook. This paper intents to contribute insightful critique of current studies on the efficacy of nanoplatforms as drug transporter, diagnostic tool and vaccine candidate against pathogenic viruses counting the highly pathogenic and incurable “coronaviruses”.
Fully Autonomous Vehicles for People with Visual Impairment
Authors: Fink Paul D. S. , Holz Jessica A. , Giudice Nicholas A.
Published: August 2021

A significant number of individuals in the United States report a disability that limits their ability to travel, including many people who are
blind or visually impaired (BVI).
The implications of restricted transportation result in negative impacts related to economic security, physical and mental health, and overall quality of life.
Fully autonomous vehicles (FAVs)
present a means to mitigate travel barriers for this population by providing new, safe, and independent travel opportunities. However, current policies governing interactions with the
artificial intelligence (AI)
‘at the wheel’ of FAVs do not reflect the accessibility needs articulated by BVI people in the extant literature, failing to encourage use cases that would result in life changing mobility. By reviewing the legislative and policy efforts surrounding FAVs, we argue that the heart of this problem is due to a disjointed, laissez-faire approach to FAV accessibility that has yet to actualize the full benefits of this new transportation mode, not only for BVI people, but also for all users. We outline the necessity for a policy framework that guides the design of FAVs to include the concerns of BVI people and then propose legislative and design recommendations aimed to promote enhanced accessibility, transparency, and fairness during FAV travel.
Client-server sessions in linear logic
Authors: Qian Zesen , Kavvos G. A. , Birkedal Lars
Published: August 2021

We introduce coexponentials, a new set of modalities for Classical Linear Logic. As duals to exponentials, the coexponentials codify a distributed form of the structural rules of weakening and contraction. This makes them a suitable logical device for encapsulating the pattern of a server receiving requests from an arbitrary number of clients on a single channel. Guided by this intuition we formulate a system of session types based on Classical Linear Logic with coexponentials, which is suited to modelling client-server interactions. We also present a session-typed functional programming language for client-server programming, which we translate to our system of coexponentials.
An existential crisis resolved: type inference for first-class existential types
Authors: Eisenberg Richard A. , Duboc Guillaume , Weirich Stephanie , Lee Daniel
Published: August 2021

Despite the great success of inferring and programming with universal types, their dual—existential types—are much harder to work with. Existential types are useful in building abstract types, working with indexed types, and providing first-class support for refinement types. This paper, set in the context of Haskell, presents a bidirectional type-inference algorithm that infers where to introduce and eliminate existentials without any annotations in terms, along with an explicitly typed, type-safe core language usable as a compilation target. This approach is backward compatible. The key ingredient is to use
strong
existentials, which support (lazily) projecting out the encapsulated data, not weak existentials accessible only by pattern-matching.
Generalized evidence passing for effect handlers: efficient compilation of effect handlers to C
Authors: Xie Ningning , Leijen Daan
Published: August 2021

This paper studies compilation techniques for algebraic effect handlers. In particular, we present a sequence of refinements of algebraic effects, going via multi-prompt delimited control, _generalized evidence passing_, yield bubbling, and finally a monadic translation into plain lambda calculus which can be compiled efficiently to many target platforms. Along the way we explore various interesting points in the design space. We provide two implementations of our techniques, one as a library in Haskell, and one as a C backend for the Koka programming language. We show that our techniques are effective, by comparing against three other best-in-class implementations of effect handlers: multi-core OCaml, the _Ev.Eff_ Haskell library, and the libhandler C library. We hope this work can serve as a basis for future designs and implementations of algebraic effects.
Calculating dependently-typed compilers (functional pearl)
Authors: Pickard Mitchell , Hutton Graham
Published: August 2021

Compilers are difficult to write, and difficult to get right. Bahr and Hutton recently developed a new technique for calculating compilers directly from specifications of their correctness, which ensures that the resulting compilers are correct-by-construction. To date, however, this technique has only been applicable to source languages that are untyped. In this article, we show that moving to a dependently-typed setting allows us to naturally support typed source languages, ensure that all compilation components are type-safe, and make the resulting calculations easier to mechanically check using a proof assistant.
Grafs: declarative graph analytics
Authors: Houshmand Farzin , Lesani Mohsen , Vora Keval
Published: August 2021

Graph analytics elicits insights from large graphs to inform critical decisions for business, safety and security. Several large-scale graph processing frameworks feature efficient runtime systems; however, they often provide programming models that are low-level and subtly different from each other. Therefore, end users can find implementation and specially optimization of graph analytics error-prone and time-consuming. This paper regards the abstract interface of the graph processing frameworks as the instruction set for graph analytics, and presents Grafs, a high-level declarative specification language for graph analytics and a synthesizer that automatically generates efficient code for five high-performance graph processing frameworks. It features novel semantics-preserving fusion transformations that optimize the specifications and reduce them to three primitives: reduction over paths, mapping over vertices and reduction over vertices. Reductions over paths are commonly calculated based on push or pull models that iteratively apply kernel functions at the vertices. This paper presents conditions, parametric in terms of the kernel functions, for the correctness and termination of the iterative models, and uses these conditions as specifications to automatically synthesize the kernel functions. Experimental results show that the generated code matches or outperforms handwritten code, and that fusion accelerates execution.
Certifying the synthesis of heap-manipulating programs
Authors: Watanabe Yasunari , Gopinathan Kiran , Pîrlea George , Polikarpova Nadia , Sergey Ilya
Published: August 2021

Automated deductive program synthesis promises to generate executable programs from concise specifications, along with proofs of correctness that can be independently verified using third-party tools. However, an attempt to exercise this promise using existing proof-certification frameworks reveals significant discrepancies in how proof derivations are structured for two different purposes: program synthesis and program verification. These discrepancies make it difficult to use certified verifiers to validate synthesis results, forcing one to write an ad-hoc translation procedure from synthesis proofs to correctness proofs for each verification backend.

In this work, we address this challenge in the context of the synthesis and verification of heap-manipulating programs. We present a technique for principled translation of deductive synthesis derivations (a.k.a. source proofs) into deductive target proofs about the synthesised programs in the logics of interactive program verifiers. We showcase our technique by implementing three different certifiers for programs generated via SuSLik, a Separation Logic-based tool for automated synthesis of programs with pointers, in foundational verification frameworks embedded in Coq: Hoare Type Theory (HTT), Iris, and Verified Software Toolchain (VST), producing concise and efficient machine-checkable proofs for characteristic synthesis benchmarks.
Getting to the point: index sets and parallelism-preserving autodiff for pointful array programming
Authors: Paszke Adam , Johnson Daniel D. , Duvenaud David , Vytiniotis Dimitrios , Radul Alexey , Johnson Matthew J. , Ragan-Kelley Jonathan , Maclaurin Dougal
Published: August 2021

We present a novel programming language design that attempts to combine the clarity and safety of high-level functional languages with the efficiency and parallelism of low-level numerical languages. We treat arrays as eagerly-memoized functions on typed index sets, allowing abstract function manipulations, such as currying, to work on arrays. In contrast to composing primitive bulk-array operations, we argue for an explicit nested indexing style that mirrors application of functions to arguments. We also introduce a fine-grained typed effects system which affords concise and automatically-parallelized in-place updates. Specifically, an associative accumulation effect allows reverse-mode automatic differentiation of in-place updates in a way that preserves parallelism. Empirically, we benchmark against the Futhark array programming language, and demonstrate that aggressive inlining and type-driven compilation allows array programs to be written in an expressive, "pointful" style with little performance penalty.
Skipping the binder bureaucracy with mixed embeddings in a semantics course (functional pearl)
Authors: Chlipala Adam
Published: August 2021

Rigorous reasoning about programs calls for some amount of bureaucracy in managing details like variable binding, but, in guiding students through big ideas in semantics, we might hope to minimize the overhead. We describe our experiment introducing a range of such ideas, using the Coq proof assistant, without any explicit representation of variables, instead using a higher-order syntax encoding that we dub "mixed embedding": it is neither the fully explicit syntax of deep embeddings nor the syntax-free programming of shallow embeddings. Marquee examples include different takes on concurrency reasoning, including in the traditions of model checking (partial-order reduction), program logics (concurrent separation logic), and type checking (session types) -- all presented without any side conditions on variables.
A comparison of methods used to quantify the work of breathing during exercise
Authors: Cross Troy J. , Gideon Elizabeth A. , Morris Sarah J. , Coriell Catherine L. , Hubbard Colin D. , Duke Joseph W.
Published: August 2021

The measurement of the work of breathing (Wb) during exercise provides us with deep insights into respiratory (patho)physiology, and sheds light on the putative factors which lead to respiratory muscle fatigue. There are 4 popular methods available to determine the Wb. Our study demonstrates that no two of these methods produce identical values of Wb during exercise. This paper also discusses the practical and theoretical limitations of each method.
Seismic Vulnerability Analysis of Rural Modified Raw‐Soil Structures
Authors: Hou Shiwei , Zhang Hao , Zhang Yuzhe , Chen Xin , Meng Suyun
Published: August 2021

Based on the concept of environmental protection of solid waste utilization, material testing is conducted to achieve native improvement using coal gangue‐based limestone‐calcined clay cement (LC3). Finite element (FE) models of rural raw‐soil architecture with a colored‐steel roof (RACSR) were established. The effect of modified soil type and seismic character on the vulnerability of single‐story raw‐soil structures was investigated using probabilistic seismic demand (PSD) analysis. The seismic response characteristics of 80 representative sequences were comparatively investigated when subjected to northwest clay (raw soil) of China, fiber and stone‐improved clay (modified soil), and coal gangue‐based limestone‐calcined clay cement (LC3 soil). The maximum interstory drift angle (ISDAmax) was lower in the LC3 soil model and the modified soil model compared to the raw‐soil model. The use of LC3 soil improves structural resistance and reduces the damage probability of a structure, and the influence of different ultimate failure states on the vulnerability of the raw‐soil structure was studied.
Liquid Force and Rupture Distance between Two Particles
Authors: Pu Cheng , Liu Fengyin , Wang Shaohan
Published: August 2021

The study of liquid force has a special meaning to industrial manufacturing. By taking the liquid bridges between equal and unequal particles as objects, the liquid force‐displacement curves were measured and recorded by using a novel Nano UTM T150 tensile system. The influences of diameter, diameter ratio, liquid volume, and the surface tension on the liquid force‐distance curve, the maximum liquid force, and rupture distance were compared and sorted. The results show that the maximum liquid force and rupture distance both increase with the increase in liquid volume, particle diameter, diameter ratio, and surface tension. The diameter plays a decisive role in determining the value of the maximum liquid force compared with surface tension and liquid volume, which only influence the force value in a local range. The rupture distance shows a positive correlation with liquid volume and surface tension and a negative correlation with the diameter or diameter ratio. The maximum liquid force between unequal particles is about half of the sum of the force between the equal spheres of larger and smaller size in that system.
A Novel Method for Developing Efficient Probability Distributions with Applications to Engineering and Life Science Data
Authors: Khalil Alamgir , Ahmadini Abdullah Ali H. , Ali Muhammad , Mashwani Wali Khan , Alshqaq Shokrya S. , Salleh Zabidin
Published: August 2021

In this paper, a new approach for deriving continuous probability distributions is developed by incorporating an extra parameter to the existing distributions. Frechet distribution is used as a submodel for an illustration to have a new continuous probability model, termed as modified Frechet (MF) distribution. Several important statistical properties such as moments, order statistics, quantile function, stress-strength parameter, mean residual life function, and mode have been derived for the proposed distribution. In order to estimate the parameters of MF distribution, the maximum likelihood estimation (MLE) method is used. To evaluate the performance of the proposed model, two real datasets are considered. Simulation studies have been carried out to investigate the performance of the parameters’ estimates. The results based on the real datasets and simulation studies provide evidence of better performance of the suggested distribution.
Laws of Gas Diffusion in Coal Particles: A Study Based on Experiment and Numerical Simulation
Authors: Hao Yongjiang , Ji Xiaofeng , Pang Jiewen
Published: August 2021

In order to research on the law of methane released through the pore in coal particles, the methane desorption experiments were conducted, respectively, on four types of particle size of coal samples under three different initial adsorption pressures. The cumulative methane desorption quantity (CMDQ) with time increasing was obtained to show that the reciprocal of CMDQ was in linear relation with the reciprocal of the square root of time, and the correlation coefficients were all above 0.99, on basis of which an empirical formula of CMDQ was established. Then, according to Fick diffusion law and Darcy percolation law, the mathematical models of methane emission from the spherical coal particles were created, respectively, and the corresponding calculating software was programmed by the finite difference method to obtain the simulated CMDQ of each sample under different conditions. The methane emission rate functions (MERF) of the simulation and the experiment were also calculated, respectively. Comparative analysis between the numerically simulated outcomes and the assay results reveals that the simulation outcomes as per Darcy’s law match the experimental data better, while the simulated results by Fick’s law deviate greatly, which indicates that the methane flowing through coal particles is more in accordance with Darcy’s law.
Cognitive Dysfunction after Heart Disease: A Manifestation of the Heart‐Brain Axis
Authors: Xu Chengyang , Tao Xueshu , Ma Xiaonan , Zhao Rui , Cao Zhipeng
Published: August 2021

The functions of the brain and heart, which are the two main supporting organs of human life, are closely linked. Numerous studies have expounded the mechanisms of the brain‐heart axis and its related clinical applications. However, the effect of heart disease on brain function, defined as the heart‐brain axis, is less studied even though cognitive dysfunction after heart disease is one of its most frequently reported manifestations. Hypoperfusion caused by heart failure appears to be an important risk factor for cognitive decline. Blood perfusion, the immune response, and oxidative stress are the possible main mechanisms of cognitive dysfunction, indicating that the blood‐brain barrier, glial cells, and amyloid‐β may play active roles in these mechanisms. Clinicians should pay more attention to the cognitive function of patients with heart disease, especially those with heart failure. In addition, further research elucidating the associated mechanisms would help discover new therapeutic targets to intervene in the process of cognitive dysfunction after heart disease. This review discusses cognitive dysfunction in relation to heart disease and its potential mechanisms.
Study on the Removal Performance of Phenol and Lead by Vernadite Synthesized via a New Method
Authors: Wang Baibing , Ouyang Nanqi , Zhang Qin , Zheng Shizhang , Li Yang , Qin Zhangjie , Luo Mimi , Jiang Guanjie
Published: August 2021

Vernadite has excellent oxidation and adsorption performance, suggesting that it has good application prospects for the removal of phenolic substances and heavy metals from wastewater. In this study, after vernadite was synthesized by two different methods, the removal performance difference between the samples synthesized by the new and traditional methods (Ver-H and Ver-OH, respectively) was explored by sample characterization, phenol degradation, and Pb2+ adsorption experiments. The results show that, compared with Ver-OH, Ver-H has a larger particle size, specific surface areas, and total organic carbon (TOC) degradation capacity; the equilibrium degradation capacity of TOC of Ver-H was increased by 31.3%. The difference in the amount of TOC degradation may be attributed to more Mn(IV) oxygen vacancies in Ver-H, which facilitate the removal of intermediate products formed during phenol degradation. In addition, the larger specific surface areas provide the mineral surface with a larger number of active sites; Ver-H can therefore adsorb more intermediate products to promote their mineralization into CO2. The adsorptions of Pb2+ by Ver-H and Ver-OH are both consistent with Langmuir isothermal adsorption, and the maximum adsorption capacities are 569.79 g/kg and 623.10 g/kg, respectively. The lack of significant difference indicates that both vernadites have strong adsorption capacities for Pb2+.
Study on Reasonable Layout of Upper Protective Layer for Prevention Rock Burst under Coal Seam Group with Close Quarters Conditions
Authors: Jin Hui-Wu , Yang Zeng-Qiang
Published: August 2021

To study the reasonable layout of upper protective layer for the prevention rock burst under coal seam group with close quarters conditions, a panel 3203 that belong to Zhongxing Colliery is taken as a typical engineering background. By means of on‐site survey, theoretical analysis, numerical simulation, and on‐site industrial applications, the reasonable layout of upper protective layer for prevention rock burst is studied. The results show that the overall stress environment of the floor under gob of upper protective layer is good, and the overall stress environment of the floor under the upper side of gob is also good, but the overall stress environment of the floor under the lower side of gob is bad. According to numerical simulation results, an L‐shaped stress superposition area is formed in the lower end of panel 3203 under the original layout scheme conditions, and the maximum stress concentration coefficient is about 2.8 in stage I and 4.0 in stage II. A new stress superposition area is formed at the middle to lower end part of advance mining face of panel 3203 for the stage II under the optimal layout scheme conditions, and the maximum stress concentration coefficient is about 2.4; the original L‐shaped stress superposition area is gone due the transfer and release of stress, and the optimal layout scheme has a very significant effect on the prevention and control of the subsequent rock burst accidents; the monitoring results of working resistance of hydraulic supports and surrounding rock deformation indicate that the overall pressure relief of the surrounding rock in advanced segment of 3205 tailgate can be effectively realized. The study conclusions provide theoretical foundation and a new guidance for preventing rock burst with similar engineering geological conditions.
FASN Knockdown Inhibited Anoikis Resistance of Gastric Cancer Cells via P-ERK1/2/Bcl-xL Pathway
Authors: Yu Li , Wang Xin , Du Yao , Zhang Xiaowen , Ling Yunzhi
Published: August 2021

Anoikis resistance (AR) is a crucial step in tumor metastasis. The overexpression of fatty acid synthase (FASN) is not only related to the AR of osteosarcoma cells, but also evidenced on gastric cancer (GC). This study investigated the role of FASN in the AR of GC cells. Plates coated with poly-HEMA were used for the culture of cells with AR. Small interfering RNA targeting FASN (siFASN) was transfected into MNK-45 and AGS cells. The number and apoptosis of cells were assessed by a hemacytometer and Annexin-V-FITC/PI assay, respectively. Aggregated cells and colony numbers were manually counted under a microscope. The migration and invasion rates were measured via wound healing and Transwell invasion assays, respectively. The levels of FASN, phosphorylated (p)-ERK1/2, ERK1/2 and Bcl-xL were detected through western blot or quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The results showed that the cell numbers of MNK-45 and AGS were increased while that of GES-1 cell was decreased during the culture in suspension. A higher apoptosis rate and a smaller number of aggregated cells were observed in GES-1 cells in comparison with MNK-45 and AGS cells. A larger colony number, greater migration and invasion rates, and higher mRNA and protein expressions of FASN were presented in the AR group compared with the control group. Cells transfected with siFASN possessed lower migration and invasion rates, reduced expressions of FASN mRNA and protein, p-ERK1/2 and Bcl-xL, and induced a significantly declined ratio of p-ERK1/2 to ERK1/2. These findings suggest that down-regulation of FASN suppresses the AR of GC cells, which may be related to the inhibition of p-ERK1/2/Bcl-xL pathway.
The Effect of Ferroptosis-Related Genes on Prognosis and Tumor Mutational Burden in Hepatocellular Carcinoma
Authors: Zhang Hao , Liu Renzheng , Sun Lin , Guo Weidong , Hu Xiao
Published: August 2021

In this study, we constructed the ferroptosis-related genes diagnostic and prognostic models. We analyzed the relationship between ferroptosis and tumor mutational burden in hepatocellular carcinoma (HCC). Eighty-four ferroptosis-related genes were analyzed by Cox regression and the least absolute shrinkage and selection operator method. Seven genes (SLC7A11, ACSL3, ACACA, SLC1A5, G6PD, ACSL6, and VDAC2) were used to construct models. The reliability of the model was verified by using the data from the ICGC database. Differential genes in high and low-risk groups revealed enrichment of many immune features by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. The degree of ferroptosis was negatively correlated with tumor mutational burden (i.e., the higher the degree of ferroptosis, the lower the tumor mutational burden). The tumor mutational burden was negatively correlated with survival. We also found that ALB, TP53, and DOCK2 may be a bridge between ferroptosis and tumor mutational burden. The reported models and the relationship with tumor mutational burden indicate new possibilities for individualized treatment of HCC patients.
Energy Efficiency Maximization for UAV‐Assisted Emergency Communication Networks
Authors: Niu Haibin , Zhao Xinyu , Hou Liming , Ma Dongjun
Published: August 2021

Using unmanned aerial vehicles (UAVs) in emergency communications is a promising technology because of their flexible deployment, low cost, and high mobility. However, due to the limited energy of the onboard battery, the service duration of the UAV is greatly limited. In this paper, we study an emerging energy‐efficient UAV emergency network, where a UAV works as an aerial base station to serve a group of users with different statistical quality‐of‐service (QoS) constraints in the downlink. In particular, the energy efficiency of the UAV is defined as the sum effective capacity of the downlink users divided by the energy consumption of the UAV, which includes the energy consumed by communication and the energy consumed by hovering. Then, we formulate an optimization problem to maximize the energy efficiency of the UAV by jointly optimizing the UAV’s altitude, downlink transmit power, and bandwidth allocation while meeting a statistical delay QoS requirement for each user. The formulated optimization problem is a nonlinear nonconvex optimization problem of fractional programming, which is difficult to solve. In order to deal with the nonconvex optimization problem, the following two steps are used. First, we transform the fractional objective function into a tractable subtractive function. Second, we decompose the original optimization problem into three subproblems, and then, we propose an efficient iterative algorithm to obtain the energy efficiency maximization value by using the Dinkelbach method, the block coordinate descent, and the successive convex optimization technique. Extensive simulation results show that our proposed algorithm has significant energy savings compared with a benchmark scheme.
Analysis and Research of Psychological Education Based on Data Mining Technology
Authors: Sang Haiyun
Published: August 2021

With the era of the Internet, linking the prevention and treatment of mental health problems in colleges and universities with the Internet will become a general trend. In order to improve the effect of identifying the psychological crisis state of college students, a method of identifying the psychological crisis state of college students based on data mining technology is proposed. First, we analyze the current research progress of college students’ psychological crisis state recognition and point out the defects of the current college students’ psychological crisis state recognition methods; then, we collect college students’ psychological crisis state data and use the support vector machine in data mining technology to analyze the psychological crisis state data. We analyze and model and then establish the recognition model of college students’ psychological crisis state; finally, we carry out the simulation experiment of college students’ psychological crisis state recognition. The experimental results show that the accuracy rate of college students’ psychological crisis state recognition by this method is over 90%, and the rejection rate and misrecognition rate are extremely low. The recognition effect is significantly better than other methods, and it can provide valuable information for college student psychological management personnel.
2D-DOA Estimation for EMVS Array with Nonuniform Noise
Authors: Cai Chang-Xin , Huang Guan-Jun , Wen Fang-Qing , Wang Xin-Hai , Wang Lin
Published: August 2021

Electromagnetic vector sensor (EMVS) array is one of the most potential arrays for future wireless communications and radars because it is capable of providing two-dimensional (2D) direction-of-arrival (DOA) estimation as well as polarization angles of the source signal. It is well known that existing subspace algorithm cannot directly be applied to a nonuniform noise scenario. In this paper, we consider the 2D-DOA estimation issue for EMVS array in the presence of nonuniform noise and propose an improved subspace-based algorithm. Firstly, it recasts the nonuniform noise issue as a matrix completion problem. The noiseless array covariance matrix is then recovered via solving a convex optimization problem. Thereafter, the shift invariant principle of the EMVS array is adopted to construct a normalized polarization steering vector, after which 2D-DOA is easily estimated as well as polarization angles by incorporating the vector cross-product technique and the pseudoinverse method. The proposed algorithm is effective to EMVS array with arbitrary sensor geometry. Furthermore, the proposed algorithm is free from the nonuniform noise. Several simulations verify the improvement of the proposed method.
Cell Traffic Prediction Based on Convolutional Neural Network for Software-Defined Ultra-Dense Visible Light Communication Networks
Authors: Zhan Shanjun , Yu Lisu , Wang Zhen , Du Yichen , Yu Yan , Cao Qinghua , Dang Shuping , Khan Zahid
Published: August 2021

With the explosive growth of ubiquitous mobile services and the advent of the 5G era, ultra-dense wireless network (UDN) architectures have entered daily production and life. However, the massive access capacity provided by 5G networks and the dense deployment of micro base stations also bring challenges such as high energy consumption, high maintenance costs, and inflexibility. Fiber-based visible light communication (FVLC) has the advantages of large bandwidth and high speed, which provides an efficient connection option for UDN. Thus, in order to make up for the poor flexibility of UDN, we propose a new FVLC-UDN architecture based on software-defined networks (SDNs). Specifically, SDN decouples the data plane and the control plane of the device and centralizes the control of the LED in the cell through a unified control plane, which can not only improve the resource allocation ability of the network but also transmit the data only as the data plane, reducing the manufacturing and implementation costs of the LED. In order to get a better resource allocation scheme, this paper proposes a model for predicting cell traffic based on convolutional neural networks. By predicting the traffic of each cell in the control domain, the traffic trend and cells’ status in the future period of time in the control domain can be obtained, so that a much more efficient resource allocation scheme can be formulated proactively to reduce energy consumption and balance communication loads. The experimental results show that on the real cell traffic dataset, this method is better than the existing prediction methods when the size of training dataset is limited.
Failure Characteristics and Mechanism of Multiface Slopes under Earthquake Load Based on PFC Method
Authors: Yang Tao , Rao Yunkang , Chen Huailin , Yang Bing , Hou Jiangrong , Zhou Zihong , Ding Haojiang
Published: August 2021

Understanding the failure mechanism and failure modes of multiface slopes in the Wenchuan earthquake can provide a scientific guideline for the slope seismic design. In this paper, the two‐dimensional particle flow code (PFC2D) and shaking table tests are used to study the failure mechanism of multiface slopes. The results show that the failure modes of slopes with different moisture content are different under seismic loads. The failure modes of slopes with the moisture content of 5%, 8%, and 12% are shattering‐shallow slip, tension‐shear slip, and shattering‐collapse slip, respectively. The failure mechanism of slopes with different water content is different. In the initial stage of vibration, the slope with 5% moisture content produces tensile cracks on the upper surface of the slope; local shear slip occurs at the foot of the slope and develops rapidly; however, a tensile failure finally occurs. In the slope with 8% moisture content, local shear cracks first develop and then are connected into the slip plane, leading to the formation of the unstable slope. A fracture network first forms in the slope with 12% moisture content under the shear action; uneven dislocation then occurs in the slope during vibration; the whole instability failure finally occurs. In the case of low moisture content, the tensile crack plays a leading role in the failure of the slope. But the influence of shear failure becomes greater with the increase of the moisture content.
Research on the Creep Characteristics of Thermal Insulation Shotcrete under the Action of Temperature and Humidity Circulation
Authors: Zhang Jinsong , Wang Yaxing , Liu Junjun , Zou Jiuqun
Published: August 2021

In order to explore the creep characteristics of thermal insulation shotcrete under the action of temperature and humidity circulation, a series of uniaxial compression creep tests were carried out with different cycles of temperature and humidity and hierarchical loading conditions. The test results show that the axial creep deformation and creep strain of the thermal insulation shotcrete specimens increase with the increase of the number of drying and wetting cycles under normal temperature water bath condition. After 28 cycles, the deformation value becomes larger obviously, and the creep strain increases greatly in the precycle period. The thermal insulation shotcrete axial steady‐state creep rate increases nonlinearly with the increase of the number of drying and wetting cycles under different stress levels. When the number of adjacent cycles is 0–3, the average increase is larger, and the axial steady‐state creep rate of thermal insulation shotcrete for 28 cycles increases with the increase of water bath temperature. The instantaneous deformation modulus of thermal insulation shotcrete decreases logarithmically with the increase of the number of drying and wetting cycles, and the total deterioration degree of the average instantaneous deformation modulus increases gradually, but the deterioration degree between adjacent cycles decreases successively. The thermal insulation shotcrete specimens with 3 cycles of fracture were mainly stretched, and with the increase of the water bath temperature, the specimen was damaged by shear failure. When the water bath temperature is 40°C, the fracture degree of the specimen increases first and then decreases with the increase of the number of cycles.
Mechanism Prediction of Astragalus membranaceus against Cisplatin-Induced Kidney Damage by Network Pharmacology and Molecular Docking
Authors: Jia Congchao , Pan Xianchao , Wang Binyou , Wang Pengyu , Wang Yiwei , Chen Rong
Published: August 2021

Background. Cisplatin is a frequently used and effective chemotherapy drug in clinical practice, but severe side effects limit its use, among which nephrotoxicity is considered the most serious and prolonged damage to the body. Astragalus membranaceus (AM) is a well-known herbal medicine, and modern pharmacological studies have confirmed its antioxidant, immunomodulatory, and antiapoptotic effects. Clinical studies have shown that AM and its active components can attenuate cisplatin-induced kidney damage, but the molecular mechanism has not been fully expounded. Materials and Methods. First, the components and targets information of AM were collected from the TCMSP, and the relevant targets of cisplatin-induced kidney damage were accessed from the GeneCards and OMIM databases. Then, the core targets were selected by the Venn diagram and network topology analysis, which was followed by GO and KEGG pathway enrichment analysis. Finally, we construct a component-target-pathway network. Furthermore, molecular docking was carried out to identify the binding activity between active components and key targets. Results. A total of 20 active components and 200 targets of AM and 646 targets related to cisplatin-induced kidney damage were obtained. 91 intersection targets were found between AM and cisplatin-induced kidney damage. Then, 16 core targets were identified, such as MAPK1, TNF-α, and p53. Furthermore, GO and KEGG pathway enrichment analysis suggested that MAPK, Toll-like receptor, and PI3K-Akt signaling pathways may be of significance in the treatment of cisplatin-induced kidney damage by AM. Molecular docking indicated that quercetin and kaempferol had high binding affinities with many core targets. Conclusion. In summary, the active components, key targets, and signaling pathways of AM in the treatment of cisplatin-induced kidney damage were predicted in this study, which contributed to the development and application of AM.
Simulation Training of E‐Sports Players Based on Wireless Sensor Network
Authors: Qian Feng
Published: August 2021

The application of wireless sensors in sports competitions is becoming more and more common. This research mainly discusses the simulation training of e‐sports players based on a wireless sensor network. Under the same experimental conditions, in order to avoid mutual influence and interference between the hand grip test and continuous endurance load, the exercise experiment for each subject was repeated twice. At the same time, the EMG signal collection and reaction time test during the endurance load are performed. All tests are data records before and after 40 minutes of the DOTA game competition. Before the start of each experimental test, the experimental equipment is calibrated and the parameters of the required indicators are set; the software was opened to run and checked whether it is normal; before the measurement, let the subjects perform simple preparation activities, train the subjects, and understand and be familiar with the action essentials required by the test to reduce the error. The original surface EMG signal recorded directly uses the built‐in signal processing function in the MR‐XP 1.08 master edition software to perform full‐wave rectification and smoothing. Processing of original EMG data: firstly, the EMG signal during endurance contraction is intercepted. In order to exclude individual differences in sEMG indicators of different subjects, the starting point is the first rise of each subject to 60% MVC or 25% MVC. The arrival time is the end point. In e‐sports, the reaction speed when the prompt is effective is significantly faster than when the prompt is invalid (p < 0.05). At this time, the time interval between the cue prompt and the target stimulus is 500 ms. This study is helpful to improve the athletes’ technical and tactical level.