bluuebunny/crossref_metadata_2025 huggingface dataset:
Social Assistance Amidst the COVID‐19 Epidemic in South Africa: A Policy Assessment
Authors: Bhorat Haroon , Oosthuizen Morné , Stanwix Ben
Published: January 2021

In an attempt to minimise the negative economic impacts of COVID‐19 on vulnerable households the South African government allocated R50 billion in additional social assistance spending. The cash transfer package included a temporary increase in existing grants and introduced a new “Covid grant.” We assess the chosen package and compare it with an initial proposal to increase the Child Support Grant (CSG). Coverage, cost and welfare effects are calculated to measure the relative impacts in each case. We find that while a significant increase in the CSG delivers resources most progressively, the addition of the COVID‐19 grant may potentially reach a much larger group of otherwise uncovered, vulnerable individuals. Critically, this extended coverage comes at a cost to the poorest households, via additional transfers to the upper income deciles. However, we identify several categories of vulnerable household groups which suggests that the workers most negatively affected by the pandemic are not necessarily those in the poorest households. The paper emphasises that social assistance to mitigate the consequences of COVID‐19 should not be viewed necessarily as a standard poverty reduction exercise, but rather as an attempt to mitigate COVID‐19‐related income shocks for the vulnerable who were most negatively affected by the pandemic.
Case series associated with COVID-19 pandemic in causing psychiatric morbidity
Authors: Mahapatra Ananya , Sharma Prerna
Published: January 2021

The COVID-19 has emerged as a public health emergency across the globe. Countries all over the world have been forced to enforce nationwide lockdowns to curb the transmission of this illness, affecting millions of people. The disorder and the lockdowns enforced have resulted in a complex set of psychosocial stressors in the lives of people, affecting their resilience and causing psychological stress and mental health issues. In this case series, we aim to highlight the role of such psychosocial stressors in causing mental health problems, especially in a vulnerable individual. The first case reports the onset of first-episode mania in a healthy individual with a family history of mental illness, after the sudden demise of the patient’s mother due to COVID-19. The second case highlights the onset of psychosis in an adolescent girl following academic stress due to the inability to carry on her education through online classes. The third case demonstrates the exacerbation of dissociative episodes in a child following the financial crisis in the family during the lockdown period. In low-income to middle-income countries such as India, there is a complex interplay of the psychosocial stressors due to the COVID-19 pandemic with pre-existing issues such as poverty, socioeconomic disparity and inequity of resources leading to a ‘double hit’ for people from disadvantaged sections of the society and individuals with pre-existing mental illness or vulnerability for mental illness.
Understory plant diversity and composition across a postfire tree density gradient in a Siberian Arctic boreal forest
Authors: Paulson Alison K. , Peña Homero , Alexander Heather D. , Davydov Sergei P. , Loranty Michael M. , Mack Michelle C. , Natali Susan M.
Published: January 2021

Cajander larch (Larix cajanderi Mayr.) forests of the Siberian Arctic are experiencing increased wildfire activity in conjunction with climate warming. These shifts could affect postfire variation in the density and arrangement of trees and understory plant communities. To better understand how understory plant composition, abundance, and diversity vary with tree density, we surveyed understory plant communities and stand characteristics (e.g., canopy cover, active layer depth, and soil organic layer depth) within 25 stands representing a density gradient of similarly-aged larch trees that established following a 1940 fire near Cherskiy, Russia. Understory plant diversity and mean total plant abundance decreased with increased canopy cover. Canopy cover was also the most important variable affecting individual species’ abundances. In general, tall shrubs (e.g., Betula nana subsp. exilis) were more abundant in low-density stands with high light availability, and mosses (e.g., Sanionia spp.) were more abundant in high-density stands with low light availability. These results provide evidence that postfire variation in tree recruitment affects understory plant community composition and diversity as stands mature. Therefore, projected increases in wildfire activity in the Siberian Arctic could have cascading impacts on forest structure and composition in both overstory and understory plant communities.
Epigenetic mechanisms influencing COVID-19
Authors: Sen Rwik , Garbati Michael , Bryant Kevin , Lu Yanan
Published: January 2021

The COVID-19 pandemic is one of the most significant public health threats in recent history and has impacted the lives of almost everyone worldwide. Epigenetic mechanisms contribute to many aspects of the SARS-CoV-2 replication cycle, including expression levels of viral receptor ACE2, expression of cytokine genes as part of the host immune response, and the implication of various histone modifications in several aspects of COVID-19. SARS-CoV-2 proteins physically associate with many different host proteins over the course of infection, and notably there are several interactions between viral proteins and epigenetic enzymes such as HDACs and bromodomain-containing proteins as shown by correlation-based studies. The many contributions of epigenetic mechanisms to the viral life cycle and the host immune response to infection have resulted in epigenetic factors being identified as emerging biomarkers for COVID-19, and project epigenetic modifiers as promising therapeutic targets to combat COVID-19. This review article highlights the major epigenetic pathways at play during COVID-19 disease and discusses ongoing clinical trials that will hopefully contribute to slowing the spread of SARS-CoV-2.
An analysis of systematic effects in finite size scaling studies using the gradient flow
Authors: Nada Alessandro , Ramos Alberto
Published: January 2021

We propose a new strategy for the determination of the step scaling function $$\sigma (u)$$

σ
(
u
)

in finite size scaling studies using the gradient flow. In this approach the determination of $$\sigma (u)$$

σ
(
u
)

is broken in two pieces: a change of the flow time at fixed physical size, and a change of the size of the system at fixed flow time. Using both perturbative arguments and a set of simulations in the pure gauge theory we show that this approach leads to a better control over the continuum extrapolations. Following this new proposal we determine the running coupling at high energies in the pure gauge theory and re-examine the determination of the $$\Lambda $$
Λ
-parameter, with special care on the perturbative truncation uncertainties.
Spin and entanglement in general relativity
Authors: Horwitz Lawrence P.
Published: January 2021

In a previous paper, we have shown how the classical and quantum relativistic dynamics of the Stueckelberg–Horwitz–Piron [SHP] theory can be embedded in general relativity (GR). We briefly review the SHP theory here and, in particular, the formulation of the theory of spin in the framework of relativistic quantum theory. We show here how the quantum theory of relativistic spin can be embedded, using a theorem of Abraham, Marsden and Ratiu and also explicit derivation, into the framework of GR by constructing a local induced representation. The relation to the work of Fock and Ivanenko is also discussed. We show that in a gravitational field there is a highly complex structure for the spin distribution in the support of the wave function. We then discuss entanglement for the spins in a two body system.
Seismic Wave Propagation in Framed Structures by Joint-Based Wave Refraction Method
Authors: Rafiee-Dehkharghani R. , Samadzad M. , Bitaraf M. , Fallahi R.
Published: January 2021

This paper studies the dynamic behavior of the structural frames subjected to seismic loadings using a joint-based wave refraction method. The beams of the frame are modeled by the Timoshenko beam theory to consider the rotary inertia and shear deformation effects. The whole frame is considered as an assemblage of the waveguides connected with joints and boundary conditions, including discrete spring–dashpots for modeling the foundation supports that are generally treated as discontinuities. The wave refraction matrices at the discontinuities are derived analytically and the final assembled system of equations are solved numerically. The accuracy of the method is validated using an experimental setup and its performance is assessed for a 15-story concrete moment frame subjected to real ground motions. The soil structure interaction effect is also considered in the simulations using discrete spring–dashpot elements. The results show that the wave refraction method can be effectively used as an alternative means for the seismic analysis of the frames. In comparison with numerical methods such as finite element method, the proposed method is computationally efficient, while its accuracy and cost are independent of the loading frequency and the length of waveguides.
Fluctuation and Frequency of the Oscillators with Exponential Spring Using Accurate Approximate Analytical Solutions
Authors: Davodi A. G. , Rezazadeh H. , Adel Waleed , Bekir A. , Ganji D. D.
Published: January 2021

This paper examines the fluctuation and frequency of the motion of a homogeneous solid on a horizontal plane on an exponential crisscross spring. The governing equations of this oscillator are investigated using a modified Homotopy Perturbation method, Energy balance method and artificial parameter–Linstedt–Poincare’ method. A comparison of solutions shows that the fluctuation and frequency of the system solved by the presented methods are effective with a minor error of 0.1%.
Common but Differentiated Strategies
Authors: Feng Renjie
Published: January 2021

The climate policies of China and India have undergone significant changes over recent years. Initially, both bluntly rejected any international mitigation obligations imposed from the outside and held industrialized countries accountable for deteriorating environmental problems. Later, as mounting scientific evidence of the devastating consequences of climate disasters became indisputable and an increasingly number of small island nations, along with Western countries, ratcheted up pressure on Beijing and New Delhi to take more vigorous climate actions, China and India began to adopt more conciliatory and cooperative attitudes toward global climate actions. At the same time, both nations’ evolving climate diplomacy is also driven by domestic realities, such as their rising economic status and growing greenhouse gas emissions. Bureaucratic establishments in the two countries’ political systems play different roles in their respective climate policy-making processes. While Beijing and New Delhi will continue to highlight their developing nation status and push advanced economies to assume the bulk of mitigation responsibilities, both have turned to more flexible policy positions, with Beijing more ready to set more ambitious targets and take on a more proactive role in global climate talks.
Challenges in Firmware Re-Hosting, Emulation, and Analysis
Authors: Wright Christopher , Moeglein William A. , Bagchi Saurabh , Kulkarni Milind , Clements Abraham A.
Published: January 2021

System emulation and firmware re-hosting have become popular techniques to answer various security and performance related questions, such as determining whether a firmware contain security vulnerabilities or meet timing requirements when run on a specific hardware platform. While this motivation for emulation and binary analysis has previously been explored and reported, starting to either work or research in the field is difficult. To this end, we provide a comprehensive guide for the practitioner or system emulation researcher. We layout common challenges faced during firmware re-hosting, explaining successive steps and surveying common tools used to overcome these challenges. We provide classification techniques on five different axes, including emulator methods, system type, fidelity, emulator purpose, and control. These classifications and comparison criteria enable the practitioner to determine the appropriate tool for emulation. We use our classifications to categorize popular works in the field and present 28 common challenges faced when creating, emulating, and analyzing a system from obtaining firmwares to post emulation analysis.
Potential Deep Learning Solutions to Persistent and Emerging Big Data Challenges—A Practitioners’ Cookbook
Authors: Mirza Behroz , Syed Tahir Q. , Khan Behraj , Malik Yameen
Published: January 2021

The phenomenon of Big Data continues to present moving targets for the scientific and technological state-of-the-art. This work demonstrates that the solution space of these challenges has expanded with deep learning now moving beyond traditional applications in computer vision and natural language processing to diverse and core machine learning tasks such as learning with streaming and non-iid-data, partial supervision, and large volumes of distributed data while preserving privacy. We present a framework coalescing multiple deep methods and corresponding models as responses to specific Big Data challenges. First, we perform a detailed per-challenge review of existing techniques, with benchmarks and usage advice, and subsequently synthesize them together into one organic construct that we discover principally uses extensions of one underlying model, the autoencoder. This work therefore provides a synthesis where challenges at scale across the Vs of Big Data could be addressed by new algorithms and architectures being proposed in the deep learning community. The value being proposed to the reader from either community in terms of nomenclature, concepts, and techniques of the other would advance the cause of multi-disciplinary, transversal research and accelerate the advance of technology in both domains.
A Systematic Review of Multimedia Tools for Cybersecurity Awareness and Education
Authors: Zhang-Kennedy Leah , Chiasson Sonia
Published: January 2021

We conduct a comprehensive review covering academic publications and industry products relating to tools for cybersecurity awareness and education aimed at non-expert end-users developed in the past 20 years. Through our search criteria, we identified 119 tools that we cataloged into five broad media categories. We explore current trends, assess their use of relevant instructional design principles, and review empirical evidence of the tools’ effectiveness. From our review, we provide an evaluation checklist and suggest that a more systematic approach to the design and evaluation of cybersecurity educational tools would be beneficial.
Context-Based Evaluation of Dimensionality Reduction Algorithms—Experiments and Statistical Significance Analysis
Authors: Ghosh Aindrila , Nashaat Mona , Miller James , Quader Shaikh
Published: January 2021

Dimensionality reduction is a commonly used technique in data analytics. Reducing the dimensionality of datasets helps not only with managing their analytical complexity but also with removing redundancy. Over the years, several such algorithms have been proposed with their aims ranging from generating simple linear projections to complex non-linear transformations of the input data. Subsequently, researchers have defined several quality metrics in order to evaluate the performances of different algorithms. Hence, given a plethora of dimensionality reduction algorithms and metrics for their quality analysis, there is a long-existing need for guidelines on how to select the most appropriate algorithm in a given scenario. In order to bridge this gap, in this article, we have compiled 12 state-of-the-art quality metrics and categorized them into 5 identified analytical contexts. Furthermore, we assessed 15 most popular dimensionality reduction algorithms on the chosen quality metrics using a large-scale and systematic experimental study. Later, using a set of robust non-parametric statistical tests, we assessed the generalizability of our evaluation on 40 real-world datasets. Finally, based on our results, we present practitioners’ guidelines for the selection of an appropriate dimensionally reduction algorithm in the present analytical contexts.
Cyclic proofs, system t, and the power of contraction
Authors: Kuperberg Denis , Pinault Laureline , Pous Damien
Published: January 2021

We study a cyclic proof system C over regular expression types, inspired by linear logic and non-wellfounded proof theory. Proofs in C can be seen as strongly typed goto programs. We show that they denote computable total functions and we analyse the relative strength of C and Gödel’s system T. In the general case, we prove that the two systems capture the same functions on natural numbers. In the affine case, i.e., when contraction is removed, we prove that they capture precisely the primitive recursive functions—providing an alternative and more general proof of a result by Dal Lago, about an affine version of system T.

Without contraction, we manage to give a direct and uniform encoding of C into T, by analysing cycles and translating them into explicit recursions. Whether such a direct and uniform translation from C to T can be given in the presence of contraction remains open.

We obtain the two upper bounds on the expressivity of C using a different technique: we formalise weak normalisation of a small step reduction semantics in subsystems of second-order arithmetic:
ACA
0
and
RCA
0
.
Efficient and provable local capability revocation using uninitialized capabilities
Authors: Georges Aïna Linn , Guéneau Armaël , Van Strydonck Thomas , Timany Amin , Trieu Alix , Huyghebaert Sander , Devriese Dominique , Birkedal Lars
Published: January 2021

Capability machines are a special form of CPUs that offer fine-grained privilege separation using a form of authority-carrying values known as capabilities. The CHERI capability machine offers local capabilities, which could be used as a cheap but restricted form of capability revocation. Unfortunately, local capability revocation is unrealistic in practice because large amounts of stack memory need to be cleared as a security precaution.

In this paper, we address this shortcoming by introducing
uninitialized capabilities
: a new form of capabilities that represent read/write authority to a block of memory without exposing the memory’s initial contents. We provide a mechanically verified program logic for reasoning about programs on a capability machine with the new feature and we formalize and prove capability safety in the form of a universal contract for untrusted code. We use uninitialized capabilities for making a previously-proposed secure calling convention efficient and prove its security using the program logic. Finally, we report on a proof-of-concept implementation of uninitialized capabilities on the CHERI capability machine.
Generating collection transformations from proofs
Authors: Benedikt Michael , Pradic Pierre
Published: January 2021

Nested relations, built up from atomic types via product and set types, form a rich data model. Over the last decades the nested relational calculus, NRC, has emerged as a standard language for defining transformations on nested collections. NRC is a strongly-typed functional language which allows building up transformations using tupling and projections, a singleton-former, and a map operation that lifts transformations on tuples to transformations on sets.

In this work we describe an alternative declarative method of describing transformations in logic. A formula with distinguished inputs and outputs gives an implicit definition if one can prove that for each input there is only one output that satisfies it. Our main result shows that one can synthesize transformations from proofs that a formula provides an implicit definition, where the proof is in an intuitionistic calculus that captures a natural style of reasoning about nested collections. Our polynomial time synthesis procedure is based on an analog of Craig's interpolation lemma, starting with a provable containment between terms representing nested collections and generating an NRC expression that interpolates between them.

We further show that NRC expressions that implement an implicit definition can be found when there is a classical proof of functionality, not just when there is an intuitionistic one. That is, whenever a formula implicitly defines a transformation, there is an NRC expression that implements it.
An approach to generate correctly rounded math libraries for new floating point variants
Authors: Lim Jay P. , Aanjaneya Mridul , Gustafson John , Nagarakatte Santosh
Published: January 2021

Given the importance of floating point (FP) performance in numerous domains, several new variants of FP and its alternatives have been proposed (e.g., Bfloat16, TensorFloat32, and posits). These representations do not have correctly rounded math libraries. Further, the use of existing FP libraries for these new representations can produce incorrect results. This paper proposes a novel approach for generating polynomial approximations that can be used to implement correctly rounded math libraries. Existing methods generate polynomials that approximate the real value of an elementary function 𝑓 (𝑥) and produce wrong results due to approximation errors and rounding errors in the implementation. In contrast, our approach generates polynomials that approximate the correctly rounded value of 𝑓 (𝑥) (i.e., the value of 𝑓 (𝑥) rounded to the target representation). It provides more margin to identify efficient polynomials that produce correctly rounded results for all inputs. We frame the problem of generating efficient polynomials that produce correctly rounded results as a linear programming problem. Using our approach, we have developed correctly rounded, yet faster, implementations of elementary functions for multiple target representations.
Giving semantics to program-counter labels via secure effects
Authors: Hirsch Andrew K. , Cecchetti Ethan
Published: January 2021

Type systems designed for information-flow control commonly use a
program-counter label
to track the sensitivity of the context and rule out data leakage arising from effectful computation in a sensitive context. Currently, type-system designers reason about this label informally except in security proofs, where they use ad-hoc techniques. We develop a framework based on monadic semantics for effects to give semantics to program-counter labels. This framework leads to three results about program-counter labels. First, we develop a new proof technique for noninterference, the core security theorem for information-flow control in effectful languages. Second, we unify notions of security for different types of effects, including state, exceptions, and nontermination. Finally, we formalize the folklore that program-counter labels are a lower bound on effects. We show that, while not universally true, this folklore has a good semantic foundation.
A verified optimizer for Quantum circuits
Authors: Hietala Kesha , Rand Robert , Hung Shih-Han , Wu Xiaodi , Hicks Michael
Published: January 2021

We present VOQC, the first fully verified optimizer for quantum circuits, written using the Coq proof assistant. Quantum circuits are expressed as programs in a simple, low-level language called SQIR, a simple quantum intermediate representation, which is deeply embedded in Coq. Optimizations and other transformations are expressed as Coq functions, which are proved correct with respect to a semantics of SQIR programs. SQIR uses a semantics of matrices of complex numbers, which is the standard for quantum computation, but treats matrices symbolically in order to reason about programs that use an arbitrary number of quantum bits. SQIR's careful design and our provided automation make it possible to write and verify a broad range of optimizations in VOQC, including full-circuit transformations from cutting-edge optimizers.
Verified code generation for the polyhedral model
Authors: Courant Nathanaël , Leroy Xavier
Published: January 2021

The polyhedral model is a high-level intermediate representation for loop nests that supports elegantly a great many loop optimizations. In a compiler, after polyhedral loop optimizations have been performed, it is necessary and difficult to regenerate sequential or parallel loop nests before continuing compilation. This paper reports on the formalization and proof of semantic preservation of such a code generator that produces sequential code from a polyhedral representation. The formalization and proofs are mechanized using the Coq proof assistant.
PerSeVerE: persistency semantics for verification under ext4
Authors: Kokologiannakis Michalis , Kaysin Ilya , Raad Azalea , Vafeiadis Viktor
Published: January 2021

Although ubiquitous, modern filesystems have rather complex behaviours that are hardly understood by programmers and lead to severe software bugs such as data corruption. As a first step to ensure correctness of software performing file I/O, we formalize the semantics of the Linux ext4 filesystem, which we integrate with the weak memory consistency semantics of C/C++. We further develop an effective model checking approach for verifying programs that use the filesystem. In doing so, we discover and report bugs in commonly-used text editors such as vim, emacs and nano.
Functorial semantics for partial theories
Authors: Di Liberti Ivan , Loregian Fosco , Nester Chad , Sobociński Paweł
Published: January 2021

We provide a Lawvere-style definition for partial theories, extending the classical notion of equational theory by allowing partially defined operations. As in the classical case, our definition is syntactic: we use an appropriate class of string diagrams as terms. This allows for equational reasoning about the class of models defined by a partial theory. We demonstrate the expressivity of such equational theories by considering a number of examples, including partial combinatory algebras and cartesian closed categories. Moreover, despite the increase in expressivity of the syntax we retain a well-behaved notion of semantics: we show that our categories of models are precisely locally finitely presentable categories, and that free models exist.
Paradoxes of probabilistic programming: and how to condition on events of measure zero with infinitesimal probabilities
Authors: Jacobs Jules
Published: January 2021

Abstract Probabilistic programming languages allow programmers to write down conditional probability distributions that represent statistical and machine learning models as programs that use observe statements. These programs are run by accumulating likelihood at each observe statement, and using the likelihood to steer random choices and weigh results with inference algorithms such as importance sampling or MCMC. We argue that naive likelihood accumulation does not give desirable semantics and leads to paradoxes when an observe statement is used to condition on a measure-zero event, particularly when the observe statement is executed conditionally on random data. We show that the paradoxes disappear if we explicitly model measure-zero events as a limit of positive measure events, and that we can execute these type of probabilistic programs by accumulating infinitesimal probabilities rather than probability densities. Our extension improves probabilistic programming languages as an executable notation for probability distributions by making it more well-behaved and more expressive, by allowing the programmer to be explicit about which limit is intended when conditioning on an event of measure zero.
A Simple Mechanism for a Budget-Constrained Buyer
Authors: Cheng Yu , Gravin Nick , Munagala Kamesh , Wang Kangning
Published: January 2021

We study a classic Bayesian mechanism design setting of monopoly problem for an additive buyer in the presence of budgets. In this setting, a monopolist seller with
m
heterogeneous items faces a single buyer and seeks to maximize her revenue. The buyer has a budget and additive valuations drawn independently for each item from (non-identical) distributions. We show that when the buyer’s budget is publicly known, it is better to sell each item separately; selling the grand bundle extracts a constant fraction of the optimal revenue. When the budget is private, we consider a standard Bayesian setting where buyer’s budget
b
is drawn from a known distribution
B
. We show that if
b
is independent of the valuations (which is necessary) and distribution
B
satisfies monotone hazard rate condition, then selling items separately or in a grand bundle is still approximately optimal.
Influence of Li Concentration-Dependent Diffusion Coefficient and Modulus Hardening on Diffusion-Induced Stresses in Anisotropic Anode Particles
Authors: Cai Xianzhong , Guo Zhansheng
Published: January 2021

Particle cracking caused by diffusion-induced stresses (DISs) is an important reason for lithium-ion battery (LIB) capacity fading. In this study, concentration-dependent material properties are introduced to model the distribution of the concentrations and evolution of DISs in anisotropic active particles. The concentration-dependent diffusion coefficient increases the concentration gradient and thus the DISs, and the concentration-dependent elastic modulus hardening increases the internal DISs and thus the stress-enhanced diffusion of Li ions. Diffusion in the direction of a large diffusion coefficient enhances the diffusion in the direction of a small diffusion coefficient, which leads to an anisotropic concentration, concentration gradient and DISs. The greater the anisotropic difference within the particles is, the more obvious the decrease in the radial stress and hoop stress. The results can be comparable with many published experimental results of graphite and indicate that the role of concentration-dependent material properties and anisotropy in the particles cannot be ignored.
The Impact of Antimony on the Performance of Antimony Doped Tin Oxide Supported Platinum for the Oxygen Reduction Reaction
Authors: Jalalpoor Daniel , Göhl Daniel , Paciok Paul , Heggen Marc , Knossalla Johannes , Radev Ivan , Peinecke Volker , Weidenthaler Claudia , Mayrhofer Karl J. J. , Ledendecker Marc , Schüth Ferdi
Published: January 2021

Antimony doped tin oxide (ATO) supported platinum nanoparticles are considered a more stable replacement for conventional carbon supported platinum materials for the oxygen reduction reaction. However, the interplay of antimony, tin and platinum and its impact on the catalytic activity and durability has only received minor attention. This is partly due to difficulties in the preparation of morphology- and surface-area-controlled antimony-doped tin oxide materials. The presented study sheds light onto catalyst–support interaction on a fundamental level, specifically between platinum as a catalyst and ATO as a support material. By using a previously described hard-templating method, a series of morphology controlled ATO support materials for platinum nanoparticles with different antimony doping concentrations were prepared. Compositional and morphological changes before and during accelerated stress tests are monitored, and underlying principles of deactivation, dissolution and catalytic performance are elaborated. We demonstrate that mobilized antimony species and strong metal support interactions lead to Pt/Sb alloy formation as well as partially blocking of active sites. This has adverse consequences on the accessible platinum surface area, and affects negatively the catalytic performance of platinum. Operando time-resolved dissolution experiments uncover the potential boundary conditions at which antimony dissolution can be effectively suppressed and how platinum influences the dissolution behavior of the support.
Applicability of Heat Generation Data in Determining the Degradation Mechanisms of Cylindrical Li-Ion Batteries
Authors: Murashko Kirill , Li Dongjiang , Danilov Dmitri L. , Notten Peter H. L. , Pyrhönen Juha , Jokiniemi Jorma
Published: January 2021

The applicability of heat generation data obtained after cylindrical Li-ion cells discharging with a constant current was analyzed thoroughly to determine cell degradation mechanisms. Different commercial and noncommercial cylindrical Li-ion cells, wherein graphite was used for negative electrode creation, were considered in this study and the degradation mechanisms were analyzed during cycling and storage. The heat generation in the cylindrical cells was estimated using heat flux and temperature measurements of the cell surface. The results obtained using analysis of the heat generation data were compared with those obtained using differential voltage analysis. The use of the heat generation data was shown to improve the detection and separation of the degradation mechanisms in Li-ion batteries during cycling and storage. The differential curve, which is based on the heat generation data, was proposed to investigate the degradation mechanisms. Moreover, the effects of the C-rate current and temperature on the form of the proposed differential curve were evaluated.
Case Study on Safety Assessment of Rockfall and Splash Stone Protective Structures for Secondary Excavation of Highway Slope
Authors: Jiang Guan , Feng Zhongju , Zhao Ruixin , Wang Fuchun , Yu Xiang , Wu Min , Zhang Zhengxu
Published: January 2021

Rockfall occurs on the excavation of the slope of highway resulting from excavated rock pieces. In order to solve the problem of rockfall protection during the disturbance of high slope secondary excavation, rockfall analysis program RocFall was used to perform inverse calculation for rockfall path of excavation disturbed rock. Based on a case study of a reconstruction and expansion project, two rockfall movement models were proposed under excavation disturbance. Moreover, the safety of protective structures under five protection schemes and different initial rockfall movement points is evaluated according to the rockfall interceptions rate. The evaluation results were further verified by long‐term field observation. The results show that the protective structure at the slope top has a better interception effect to rockfall. It was difficult to intercept the splash stone, which threats to the traffic safety of the existing roads. According to different construction points of mechanical excavation and the interception rate of splash stone by the protective structure, the forbidden region and safety region of mechanical excavation were proposed.
Effects of Sudden Temperature Drop on Stress at Rapidly Repaired Bonding Interface of Pavement
Authors: Wang Le-fan , Xing-zhong Weng , Li Ye , Liang Le , Li Wan
Published: January 2021

The numerical simulations were employed to establish an edge-corner repair model with magnesium phosphate cement (MPC) concrete as the repair material and ordinary Portland cement concrete as the old pavement. After the simulation of repair construction by using MPC concrete with different coarse aggregates, the effect of sudden temperature drop during the stable stage of hydration reaction on the stress distribution at each bonding interface was analyzed. The numerical calculations indicate that the sudden temperature drop led to temperature-induced stress on the bonding interfaces. The stress distribution at each bonding interface was obtained and the maximum principal stress at each bonding interface was at the intersection angle of three bonding interfaces. The relationship between the temperature and stress at each bonding interface was found when different coarse aggregates were used to prepare the repairing material. Also, the effect of different coarse aggregates on the bonding interface of the repairing material was obtained when basalt was the coarse aggregate of old concrete. The stability of bonding surface from best to worst was as follows: basalt > limestone > granite > conglomerate > sandstone > quartzite.
An Inertial Method for Split Common Fixed Point Problems in Hilbert Spaces
Authors: Zhang Haixia , Cui Huanhuan
Published: January 2021

In this paper, we consider the split common fixed point problem in Hilbert spaces. By using the inertial technique, we propose a new algorithm for solving the problem. Under some mild conditions, we establish two weak convergence theorems of the proposed algorithm. Moreover, the stepsize in our algorithm is independent of the norm of the given linear mapping, which can further improve the performance of the algorithm.
Model of Charged Anisotropic Strange Stars in Minimally Coupled
f

R

Gravity
Authors: Nazar H. , Abbas G.
Published: January 2021

In the present article, we have investigated a new family of nonsingular solutions of static relativistic compact sphere which incorporates the characteristics of anisotropic fluid and electromagnetic field in the context of minimally coupled

f

R

theory of gravity. The strange matter

MIT

bag model equation of state (EoS) has been considered along with the usual forms of the Karori–Barua

KB

metric potentials. For this purpose, we derived the Einstein–Maxwell field equations in the assistance of strange matter EoS and

KB

type ansatz by employing the two viable and cosmologically well-consistent models of

f

R

=
R
+
γ

R

2

and

f

R

=
R
+
γ
R

R
+
α

R

2

. Thereafter, we have checked the physical acceptability of the proposed results such as pressure, energy density, energy conditions,

TOV

equation, stability conditions, mass function, compactness, and surface redshift by using graphical representation. Moreover, we have investigated that the energy density and radial pressure are nonsingular at the core or free from central singularity and always regular at every interior point of the compact sphere. The numerical values of such parameters along with the surface density, charge to radius ratio, and bag constant are computed for three well-known compact stars such as

CS1

SAXJ
1808
.
4
−
3658

(

x
˜

=
7.07
 
km

,

CS2

VelaX
−
1

x
˜

=
9.56
 
km

, and

CS3

4U1820
−
30

x
˜

=
10
 
km

and are presented in Tables 1–6. Conclusively, we have noticed that our presented charged compact stellar object in the background of two well-known

f

R

models obeys all the necessary conditions for the stable equilibrium position and which is also perfectly fit to compose the strange quark star object.
The Environmental Effects Induced by a Metro Shield Tunnel Side‐Crossing on Adjacent Pile Foundations and Its Impact Partition
Authors: Hu Hui , Zhu Yimo , Zhang Gang , Zhang Heng , Tu Peng
Published: January 2021

With the advantages of fast construction speed and small disturbance to stratum, shield tunneling is becoming the preferred construction scheme for metro construction. However, if the disturbance of stratum cannot be clearly understood, it will affect the safety of adjacent underground structures and aboveground buildings. Based on the construction of the interval tunnel between Shizishan station and Chuanshi station of Chengdu metro line 7 project, this paper proposed a simplified calculation method to analyze the impact of shield excavation on adjacent pile foundation. A two‐stage method of modified Peck formula and Winkler elastic foundation model was used to investigate the additional displacement and internal force of pile. A three‐dimensional numerical model validated with the field test data was performed to compare with the theoretical results. The impact factors and their impact degree were discussed. The results show that the additional displacement and internal force are at a reasonable and acceptable level. The permanent pile foundation should adopt the small diameter pile as far as possible. When the small diameter pile foundation cannot meet the stress requirements, the design scheme of the pile group should be adopted. The area around shield tunnel is divided into strong impact area of pile foundation (S ≤ 0.75 D), slight impact area (0.75 D ≤ S ≤ 1.5 D), and no impact area (S > 1.5 D). The pile researched in this paper (S = 0.83 D) is in the slight impact area.
Toxic Prediction of Pyrrolizidine Alkaloids and Structure‐Dependent Induction of Apoptosis in HepaRG Cells
Authors: Zheng Pimiao , Xu Yuliang , Ren Zhenhui , Wang Zile , Wang Sihan , Xiong Jincheng , Zhang Huixia , Jiang Haiyang
Published: January 2021

Pyrrolizidine alkaloids (PAs) are common phytotoxins and could cause liver genotoxicity/carcinogenicity following metabolic activation. However, the toxicity of different structures remains unclear due to the wide variety of PAs. In this study, the absorption, distribution, metabolism, excretion, and toxicity (ADMET) of 40 PAs were analyzed, and their toxicity was predicted by Komputer Assisted Technology (TOPKAT) using Discovery Studio software. The in silico results showed that all PAs except retronecine had good intestinal absorption, and all PAs were predicted to have different toxicity ranges. To verify the predictive results, 4 PAs were selected to investigate cell injury and possible mechanisms of the differentiation in HepaRG cells, including retronecine type of twelve‐membered cyclic diester (retrorsine), eleven‐membered cyclic diester (monocrotaline), noncyclic diester (retronecine), and platynecine type (platyphylline). After 24 h exposure, retronecine‐type PAs exhibited concentration‐dependent cytotoxicity. The high‐content screening assay showed that cell oxidative stress, mitochondrial damage, endoplasmic reticulum stress, and the concentration of calcium ions increased, and neutral lipid metabolism was changed notably in HepaRG cells. Induced apoptosis by PAs was indicated by cell cycle arrest in the G2/M phase, disrupting the mitochondrial membrane potential. Overall, our study revealed structure‐dependent cytotoxicity and apoptosis after PA exposure, suggesting that the prediction results of in silico have certain reference values for compound toxicity. A 1,2‐membered cyclic diester seems to be a more potent apoptosis inducer than other PAs.
Language Development in Turkish-Dutch Bilingual Children
Authors: D’haeseleer Evelien , Daelman Julie , Altinkamis Feyza , Smet Anne-Sophie , Ryckaert Elise , Van Lierde Kristiane
Published: January 2021

Introduction: In the current literature, there is a well-established necessity for the improvement of bilingual language diagnostics. Nowadays, the majority of clinicians in Belgium still rely on standardized tests with monolingual norm samples. It is therefore fundamental to have a detailed knowledge of the performance of bilingual children on these monolingual normed tests. Furthermore, there is also a need for unambiguous longitudinal research on the language performances of bilingual children. Therefore, this study aims to investigate the language skills of 25 Turkish-Dutch successive bilinguals compared to 25 age- and gender-matched monolingual Dutch children. In 9 bilinguals and 13 monolinguals, longitudinal data of 3 years (at 6 years and at 9 years) were collected and compared. Methods: The subject group consisted of 25 bilingual Turkish-Dutch children with a mean age of 9 years and 6 months (SD 0.26 years, min. 8 years and 11 months to max. 9 years and 10 months) with Turkish as the dominant home language. Language exposure to Dutch was at least 3 years. An age- and gender-matched control group of 25 monolingual Dutch children with same educational backgrounds was compiled. Language skills were investigated using the Dutch version of the CELF. In 22 children, language skills were reassessed 3 years later in a follow-up study. Data were compared using the Mann-Whitney U test and Wilcoxon matched-pairs signed-rank test. Results: Language comprehension and production were significantly lower in the bilingual children compared to the monolinguals. After 3 years, the language delay in bilingual Turkish-Dutch children remained the same. Language production in the bilingual children was mainly influenced by the profession of the mother and the home language. Conclusion: The low performances of typically developing Turkish-Dutch children on language batteries are worrying and have clinical implications. The same language gap was found at the age of 6 and 9 years in Turkish-Dutch bilingual children compared to monolingual Dutch children, implying that the bilingual children did not catch up with their peers.
Michel Riaudel sobre Ana Cristina Cesar
Authors: Galvão Raquel Machado
Published: January 2021

Entrevista realizada com o professor, tradutor e pesquisador francês Michel Riaudel em junho de 2019. O diálogo parte de questões e de teorias apresentadas na sua tese sobre Ana Cristina Cesar, a fim de revisar as dimensões da obra e das pesquisas a respeito da produção da escritora na atualidade. As perspectivas de leituras apresentadas por Riaudel na conversa abrangem as influências literárias, o aspecto do engajamento literário, as reflexões relacionadas à escrita feminina e a relação entre tradução e criação no percurso intelectual da poeta.
DO ESCOAMENTO À PRESENÇA
Authors: Minkovicius Dani Barki
Published: January 2021

O artigo propõe, a partir do estudo de diversos escritos de Pascal, se voltar ao que o pensador seiscentista teria considerado acerca do tempo e da eternidade: o que seriam, se e como se relacionariam. Para tanto, será esboçado, primeiramente, um percurso que passará pelo estudo da condição humana, com a descrição de sua situação de desproporção e miséria, e da condição das coisas da vida mundana também, ademais ao homem, até se chegar à compreensão da existência de uma outra ordem; o que marcará, então, um percurso do tempo à eternidade, ou, como se verá, do escoamento à presença.
UNIVOCIDAD VERSUS DUALIDAD EN SPINOZA
Authors: Garcia Ruzo Antonieta
Published: January 2021

El presente trabajo aborda el problema dualista en la ontología spinoziana. Éste pretende reconstruir brevemente la historia de la discusión en torno a esta problemática, con el fin de analizar en qué términos interpretó la tradición las duplas esencia-existencia, eternidad-duración, infinito-finito, sustancia-modos. El objetivo será poner de manifiesto los errores que surgen tanto de entender estas distinciones como ontológicas, como de ignorarlas. La apuesta será, en cambio, la de una lectura que permita reivindicar la dualidad en Spinoza, pero que deje ver en qué sentido esta es una dualidad gnoseológica y no ontológica. Es decir, mostrar de qué manera las duplas que encontramos a lo largo de la obra de Spinoza refieren a perspectivas o modos de conocer lo real, y no a estratos del ser. Creemos que, de este modo, la tan denostada dualidad no sólo se vuelve compatible con la univocidad del ser, sino que permite una comprensión más acabada del auténtico espíritu spinozista.
PENÚRIA DAS PALAVRAS
Authors: Ramos Carmel da Silva
Published: January 2021

A radical crítica à linguagem efetuada por Spinoza, que insiste em seu necessário potencial falsificador, parece equipará-lo aos seus contemporâneos. Mais do que isso, parece introduzir um problema insolúvel para a possibilidade de comunicação unívoca da verdade – incluindo a expressão dA radical crítica à linguagem efetuada por Spinoza, que insisteem seu necessário potencial falsificador, parece equipará-lo aos seus contemporâneos. Mais do que isso, parece introduzir um problema insolúvel para a possibilidade de comunicação unívoca da verdade — incluindo a expressão de sua própria filosofia. Neste artigo, procuro refletir sobre esta crítica e propor uma alternativa ao caráter imaginativo das palavras, apostando na distinção entre linguagem e método. Esta propostainterpretativa permitirá reclassificar a posição spinozista e manter sua originalidade frente às demais concepções de seu período histórico.e sua própria filosofia. Neste artigo, procuro refletir sobre esta crítica e propor uma alternativa ao caráter imaginativo das palavras, apostando na distinção entre linguagem e método. Esta proposta interpretativa permitirá reclassificar a posição spinozista e manter sua originalidade frente às demais concepções de seu período histórico.