bluuebunny/crossref_metadata_2025 huggingface dataset:
Peer mentorship to improve self-management of hip and knee osteoarthritis: a randomised feasibility trial
Authors: Anderson Anna M , Lavender Elizabeth C , Dusabe-Richards Esther , Mebrahtu Teumzghi F , McGowan Linda , Conaghan Philip G , Kingsbury Sarah R , Richardson Gerry , Antcliff Deborah , McHugh Gretl A
Published: July 2021

Objective

To determine the feasibility of conducting a randomised controlled trial (RCT) of a peer mentorship intervention to improve self-management of osteoarthritis (OA).

Design

Six-month parallel group non-blinded randomised feasibility trial.

Setting

One secondary care and one primary care UK National Health Service Trust.

Participants

Fifty adults aged ≥55 years old with hip and/or knee OA.

Interventions

Participants were allocated 1:1 to the intervention or control group using an online randomisation service. Intervention group participants received usual care (information resources) and up to eight community-based self-management support sessions delivered by a peer mentor (trained volunteer with hip and/or knee OA). Control group participants received usual care only.

Outcome measures

Key feasibility outcomes were participant and peer mentor recruitment and attrition, intervention completion and the sample size required for a definitive RCT. Based on these feasibility outcomes, four success criteria for proceeding to a definitive RCT were prespecified. Patient-reported outcomes were collected via questionnaires at baseline, 8 weeks and 6 months.

Results

Ninety-six individuals were screened, 65 were eligible and 50 were randomised (25 per group). Of the 24 participants who commenced the intervention, 20 completed it. Four participants did not complete the 6-month questionnaire. Twenty-one individuals were eligible for the peer mentor role, 15 were trained and 5 withdrew prior to being matched with a participant. No intervention-related harms occurred. Allowing for 20% attrition, the sample size required for a definitive RCT was calculated as 170 participants. The intervention group showed improvements in self-management compared with the control group.

Conclusions

The feasibility outcomes achieved the prespecified criteria for proceeding to an RCT. The exploratory analyses suggest peer mentorship may improve OA self-management. An RCT of the OA peer mentorship intervention is therefore warranted with minor modifications to the intervention and trial procedures.

Trial registration number

ISRCTN:50675542.
Non-invasive, vagus nerve stimulation to reduce ileus after colorectal surgery: protocol for a feasibility trial with nested mechanistic studies
Authors: Chapman Stephen J , Naylor Maureen , Czoski Murray Carolyn J , Tolan Damian , Stocken Deborah D , Jayne David G
Published: July 2021

Introduction

Ileus is a common and distressing condition characterised by gut dysfunction after surgery. While a number of interventions have aimed to curtail its impact on patients and healthcare systems, ileus is still an unmet challenge. Electrical stimulation of the vagus nerve is a promising new treatment due to its role in modulating the neuro-immune axis through a novel anti-inflammatory reflex. The protocol for a feasibility study of non-invasive vagus nerve stimulation (nVNS), and a programme of mechanistic and qualitative studies, is described.

Methods and analysis

This is a participant-blinded, parallel-group, randomised, sham-controlled feasibility trial (IDEAL Stage 2b) of self-administered nVNS. One hundred forty patients planned for elective, minimally invasive, colorectal surgery will be randomised to four schedules of nVNS before and after surgery. Feasibility outcomes include assessments of recruitment and attrition, adequacy of blinding and compliance to the intervention. Clinical outcomes include bowel function and length of hospital stay. A series of mechanistic substudies exploring the impact of nVNS on inflammation and bowel motility will inform the design of the final stimulation schedule. Semistructured interviews with participants will explore experiences and perceptions of the intervention, while interviews with patients who decline participation will explore barriers to recruitment.

Ethics and dissemination

The protocol has been approved by the Tyne and Wear South National Health Service (NHS) Research Ethics Committee (19/NE/0217) on 2 July 2019. Feasibility, mechanistic and qualitative findings will be disseminated to national and international partners through peer-reviewed publications, academic conferences, social media channels and stakeholder engagement activities. The findings will build a case for or against progression to a definitive randomised assessment as well as informing key elements of study design.

Trial registration number

ISRCTN62033341.
External validation of simplified out-of-hospital cardiac arrest and cardiac arrest hospital prognosis scores in a Japanese population: a multicentre retrospective cohort study
Authors: Shibahashi Keita , Sugiyama Kazuhiro , Kuwahara Yusuke , Ishida Takuto , Sakurai Atsushi , Kitamura Nobuya , Tagami Takashi , Nakada Taka-aki , Takeda Munekazu , Hamabe Yuichi
Published: July 2021

Background

The novel simplified out-of-hospital cardiac arrest (sOHCA) and simplified cardiac arrest hospital prognosis (sCAHP) scores used for prognostication of hospitalised patients have not been externally validated. Therefore, this study aimed to externally validate the sOHCA and sCAHP scores in a Japanese population.

Methods

We retrospectively analysed data from a prospectively maintained Japanese database (January 2012 to March 2013). We identified adult patients who had been resuscitated and hospitalised after intrinsic out-of-hospital cardiac arrest (OHCA) (n=2428, age ≥18 years). We validated the sOHCA and sCAHP scores with reference to the original scores in predicting 1-month unfavourable neurological outcomes (cerebral performance categories 3–5) based on the discrimination and calibration measures of area under the receiver operating characteristic curves (AUCs) and a Hosmer-Lemeshow goodness-of-fit test with a calibration plot, respectively.

Results

In total, 1985/2484 (82%) patients had a 1-month unfavourable neurological outcome. The original OHCA, sOHCA, original cardiac arrest hospital prognosis (CAHP) and sCAHP scores were available for 855/2428 (35%), 1359/2428 (56%), 1130/2428 (47%) and 1834/2428 (76%) patients, respectively. The AUCs of simplified scores did not differ significantly from those of the original scores, whereas the AUC of the sCAHP score was significantly higher than that of the sOHCA score (0.88 vs 0.81, p<0.001). The goodness of fit was poor in the sOHCA score (ν=8, χ2=19.1 and Hosmer-Lemeshow test: p=0.014) but not in the sCAHP score (ν=8, χ2=13.5 and Hosmer-Lemeshow test: p=0.10).

Conclusion

The performances of the original and simplified OHCA and CAHP scores in predicting neurological outcomes in successfully resuscitated OHCA patients were acceptable. With the highest availability, similar discrimination and good calibration, the sCAHP score has promising potential for clinical implementation, although further validation studies to evaluate its clinical acceptance are necessary.
Moral motivation regarding dementia risk testing among affected persons in Germany and Israel
Authors: Alpinar-Sencan Zümrüt , Schicktanz Silke , Ulitsa Natalie , Shefet Daphna , Werner Perla
Published: July 2021

Recent advances in biomarkers may soon make it possible to identify persons at high risk for late-onset Alzheimer’s disease at a presymptomatic (preclinical) stage. Popular demand for testing is increasing despite the lack of cure and effective prevention options and despite uncertainties regarding the predictive value of biomarker tests. This underscores the relevance of the ethical, cultural and social implications of predictive testing and the need to advance the bioethical debate beyond considerations of clinical consequences. Our qualitative study included three groups of affected persons: People with mild neurocognitive disorder, their relatives and family caregivers of people with dementia. We explored their moral motivations regarding predictive, biomarker-based testing and preclinical diagnostics. We interviewed affected individuals in Germany and Israel (N=88; 44 participants in each country). Transcripts of 12 focus groups and 12 semistructured interviews were content analysed with a focus on the moral motivations of affected persons in their justification of why they accept or reject predictive testing and early diagnosis. We grouped the underlying aspects of moral motivation into four ethical categories: beneficence as a form of personal utility focusing on well-being, the ties of responsibility linking families and their individual members, the importance of self-determination by later life planning and notions of a good life. In general, cultural parallels among these motives were very obvious. Cultural variation occurred mainly in openness to suicide, scepticism about test validity and emphasis on personal autonomy. The study underscores the importance of counselling for life-planning issues and of informing test candidates about problems with test validity and about the ambiguity of test results.
What became of the ‘eyes and the ears’?: exploring the challenges to reporting poor quality of care among trainee medical staff
Authors: Berry Philip
Published: July 2021

The importance of trainee medical staff in alerting Trusts to patient safety risks and low-quality care was established by the Francis Report, yet many remain hesitant about speaking up. Known barriers include lack of feedback, sceptical attitudes to the likelihood of change and fear of consequences. The author explores other factors including moral orientation in the workplace, role modelling by senior clinicians, discontinuity, ‘normalisation of deviance’, human reactions to burnout/moral injury, loyalty and the spectrum of motivation. The issues of absent feedback and fear are discussed in detail. Challenges met by those receiving reports are also described, such as how to collate soft intelligence, putting concerns into context (the ‘bigger picture’) and stewardship of resources. Initiatives to encourage reporting of trainees’ concerns such as speak up guardians, ‘Speak Up for Safety’ campaign and simulation training are described. A proposal to embed proactive intelligence-gathering arrangements is presented.
Randomized comparison between pericapsular nerve group (PENG) block and suprainguinal fascia iliaca block for total hip arthroplasty
Authors: Aliste Julián , Layera Sebastián , Bravo Daniela , Jara Álvaro , Muñoz Gonzalo , Barrientos Cristián , Wulf Rodrigo , Brañez Julián , Finlayson Roderick J , Tran De Q
Published: July 2021

Background

This randomized trial compared ultrasound-guided pericapsular nerve group block and suprainguinal fascia iliaca block in patients undergoing primary total hip arthroplasty. We selected the postoperative incidence of quadriceps motor block (defined as paresis or paralysis of knee extension) at 6 hours as the primary outcome. We hypothesized that, compared with suprainguinal fascia iliaca block, pericapsular nerve group block would decrease its occurrence from 70% to 20%.

Methods

Forty patients undergoing primary total hip arthroplasty under spinal anesthesia were randomly allocated to receive a pericapsular nerve group block (n=20) using 20 mL of adrenalized levobupivacaine 0.50%, or a suprainguinal fascia iliaca block (n=20) using 40 mL of adrenalized levobupivacaine 0.25%. After the performance of the block, a blinded observer recorded pain scores at 3, 6, 12, 18, 24, 36, and 48 hours; cumulative breakthrough morphine consumption at 24 and 48 hours; opioid-related side effects; ability to perform physiotherapy at 24 and 48 hours; as well as length of stay. Furthermore, the blinded observer also carried out sensory assessment (of the anterior, lateral, and medial aspects of the mid-thigh) and motor assessment (knee extension and hip adduction) at 3, 6, and 24 hours.

Results

Compared with suprainguinal fascia iliaca block, pericapsular nerve group block resulted in a lower incidence of quadriceps motor block at 3 hours (45% vs 90%; p<0.001) and 6 hours (25% vs 85%; p<0.001). Furthermore, pericapsular nerve group block also provided better preservation of hip adduction at 3 hours (p=0.023) as well as decreased sensory block of the anterior, lateral, and medial thighs at all measurement intervals (all p≤0.014). No clinically significant intergroup differences were found in terms of postoperative pain scores, cumulative opioid consumption at 24 and 48 hours, ability to perform physiotherapy, opioid-related side effects, and length of hospital stay.

Conclusion

For primary total hip arthroplasty, pericapsular nerve group block results in better preservation of motor function than suprainguinal fascia iliaca block. Additional investigation is required to elucidate the optimal local anesthetic volume for motor-sparing pericapsular nerve group block and to compare the latter with alternate motor-sparing strategies such as periarticular local anesthetic infiltration.

Trial registration number

NCT04402450.
Development and pilot testing of the Nutrition Attitudes and Knowledge Questionnaire to measure changes of child nutrition knowledge related to the Canada’s Food Guide
Authors: Franco-Arellano Beatriz , Brown Jacqueline M. , Froome Hannah M. , LeSage Ann , Arcand JoAnne
Published: July 2021

Foodbot Factory is a serious game developed to teach children about the 2019 Canada’s Food Guide (CFG) healthy eating principles. Because no measurement tools existed to assess changes in children’s knowledge of the CFG, the Nutrition Attitudes and Knowledge (NAK) questionnaire was developed for this purpose. The NAK is based on the 2019 CFG nutrition content and aligned with the Foodbot Factory modules (Drinks, Whole Grain foods, Vegetables and Fruit, Protein foods). Seven experts assessed face and content validity of the draft NAK questionnaire. Three sections were deemed valid, while the remaining 2 required minor revisions. The NAK was pilot tested for changes in nutrition attitudes and knowledge among children aged 9–10 years-old (n = 23), who answered the NAK questionnaire before and after using Foodbot Factory. Significant increases were found in overall nutrition knowledge, and knowledge of Whole Grain foods, Vegetables and Fruit and Protein foods. Knowledge of Drinks and nutrition attitudes remained unchanged. The NAK showed a moderate reliability when tested among a group of children (n = 23). While the NAK questionnaire is a promising tool for assessing changes nutrition knowledge related to the 2019 CFG guidelines in children, further research is required to test construct validity of this instrument.

Novelty: The Nutrition Attitudes and Knowledge (NAK) questionnaire was developed by educators and dietitians. The NAK underwent face and content validity assessments and was pilot tested among children. The NAK questionnaire is a potential tool to detect changes in children’s knowledge of the 2019 Canada’s Food Guide.
CD142 plays a key role in the carcinogenesis of gastric adenocarcinoma by inhibiting BCL2-dependent autophagy
Authors: Xu Weifeng , Chen Beibei , Ke Dianshan , Chen Xiaobing
Published: July 2021

CD142 is expressed on the surface of multiple malignant tumors and contributes to carcinogenesis. However, the role of CD142 in the pathogenesis of gastric adenocarcinoma (GAC) remains unclear. This study aimed to investigate the role of CD142 in GAC carcinogenesis. Our results showed that CD142 expression was significantly increased in GAC cancer tissues, especially in those with significant invasion or metastasis. The invasion and migration of CD142-positive SNU16 cells was significantly increased compared to that of CD142-negative cells. Moreover, CD142 overexpression promoted the invasion and migration of SGC083 cells, but CD142 silencing had the opposite effect. In addition, there was a positive correlation between CD142 expression in cancer tissues and serum Interleukin-8 (IL-8) levels. CD142 overexpression promoted IL-8 production in SGC083 cells. In vivo analysis showed that the implantation of CD142-positive SNU16 cells promoted the growth of xenograft tumor and the production of IL-8. Mechanistically, CD142 silencing not only inhibited the expression of BCL2 and the interaction between BCL2 and Beclin1, but also promoted the autophagic response in SGC083. Furthermore, CD142 silencing-induced IL-8 degradation was recovered by treatment with the autophagy inhibitor, 3-MA. CD142 can inhibit autophagic cell death and autophagic degradation of IL-8 in GAC, which exerts an effect on GAC carcinogenesis.
Ruppeiner geometry and thermodynamic phase transition of the black hole in massive gravity
Authors: Wu Bin , Wang Chao , Xu Zhen-Ming , Yang Wen-Li
Published: July 2021

The phase transition and thermodynamic geometry of a 4-dimensional AdS topological charged black hole in de Rham, Gabadadze and Tolley (dRGT) massive gravity have been studied. After introducing a normalized thermodynamic scalar curvature, it is speculated that its value is related to the interaction between the underlying black hole molecules if the black hole molecules exist. We show that there does exist a crucial parameter given in terms of the topology, charge, and massive parameters of the black hole, which characterizes the thermodynamic properties of the black hole. It is found that when the parameter is positive, the singlet large black hole phase does not exist for sufficient low temperature and there is a weak repulsive interaction dominating for the small black hole which is similar to the Reissner–Nordström AdS black hole; when the parameter is negative, an additional phase region describing large black holes also implies a dominant repulsive interaction. These constitute the distinguishable features of dRGT massive topological black hole from those of the Reissner–Nordström AdS black hole as well as the Van der Waals fluid system.
Unifying dark matter and dark energy with non-canonical scalars
Authors: Mishra Swagat S. , Sahni Varun
Published: July 2021

Non-canonical scalar fields with the Lagrangian $${{\mathcal {L}}} = X^\alpha - V(\phi )$$

L
=

X
α

-
V

(
ϕ
)

, possess the attractive property that the speed of sound, $$c_s^{2} = (2\,\alpha - 1)^{-1}$$

c
s
2

=

(
2

α
-
1
)

-
1

, can be exceedingly small for large values of $$\alpha $$
α
. This allows a non-canonical field to cluster and behave like warm/cold dark matter on small scales. We derive a general condition on the potential in order to facilitate the kinetic term $$X^\alpha $$

X
α

to play the role of dark matter, while the potential term $$V(\phi )$$

V
(
ϕ
)

playing the role of dark energy at late times. We demonstrate that simple potentials including $$V= V_0\coth ^2{\phi }$$

V
=

V
0

coth
2

ϕ

and a Starobinsky-type potential can unify dark matter and dark energy. Cascading dark energy, in which the potential cascades to lower values in a series of discrete steps, can also work as a unified model.
Gravitational lensing by a quantum deformed Schwarzschild black hole
Authors: Lu Xu , Xie Yi
Published: July 2021

We investigate the weak and strong deflection gravitational lensing by a quantum deformed Schwarzschild black hole and find their observables. These lensing observables are evaluated and the detectability of the quantum deformation is assessed, after assuming the supermassive black holes Sgr A* and M87* respectively in the Galactic Center and at the center of M87 as the lenses. We also intensively compare these findings with those of a renormalization group improved Schwarzschild black hole and an asymptotically safe black hole. We find that, among these black holes, it is most likely to test the quantum deformed Schwarzschild black hole via its weak deflection lensing observables in the foreseen future.
Time–Frequency Decomposition of Scalp Electroencephalograms Improves Deep Learning-Based Epilepsy Diagnosis
Authors: Thangavel Prasanth , Thomas John , Peh Wei Yan , Jing Jin , Yuvaraj Rajamanickam , Cash Sydney S. , Chaudhari Rima , Karia Sagar , Rathakrishnan Rahul , Saini Vinay , Shah Nilesh , Srivastava Rohit , Tan Yee-Leng , Westover Brandon , Dauwels Justin
Published: July 2021

Epilepsy diagnosis based on Interictal Epileptiform Discharges (IEDs) in scalp electroencephalograms (EEGs) is laborious and often subjective. Therefore, it is necessary to build an effective IED detector and an automatic method to classify IED-free versus IED EEGs. In this study, we evaluate features that may provide reliable IED detection and EEG classification. Specifically, we investigate the IED detector based on convolutional neural network (ConvNet) with different input features (temporal, spectral, and wavelet features). We explore different ConvNet architectures and types, including 1D (one-dimensional) ConvNet, 2D (two-dimensional) ConvNet, and noise injection at various layers. We evaluate the EEG classification performance on five independent datasets. The 1D ConvNet with preprocessed full-frequency EEG signal and frequency bands (delta, theta, alpha, beta) with Gaussian additive noise at the output layer achieved the best IED detection results with a false detection rate of 0.23/min at 90% sensitivity. The EEG classification system obtained a mean EEG classification Leave-One-Institution-Out (LOIO) cross-validation (CV) balanced accuracy (BAC) of 78.1% (area under the curve (AUC) of 0.839) and Leave-One-Subject-Out (LOSO) CV BAC of 79.5% (AUC of 0.856). Since the proposed classification system only takes a few seconds to analyze a 30-min routine EEG, it may help in reducing the human effort required for epilepsy diagnosis.
FRACTAL ANALYSES OF THE SHAPE FACTOR IN KOZENY–CARMAN EQUATION FOR HYDRAULIC PERMEABILITY IN HYDRATE-BEARING SEDIMENTS
Authors: LIU LELE , SUN QICHENG , WU NENGYOU , LIU CHANGLING , NING FULONG , CAI JIANCHAO
Published: July 2021

Hydraulic permeability in hydrate-bearing sediments largely controlling the rate of gas production from hydrate deposits is widely estimated by various modified models based on the Kozeny–Carman equation. However, the effect of hydrate saturation on the shape factor in the Kozeny–Carman equation is not fully understood. In this study, a fractal model of the shape factor is theoretically derived to show physical relations between the shape factor and fractal parameters of fluid occupied pores. Then, verification of the model is performed, and effects of intrinsic porosity, intrinsic pore area and tortuosity fractal dimensions on the hydrate saturation dependent shape factor are analyzed. Finally, how weighted specific surface areas evolve with hydrate saturation is theoretically discussed, and results are further applied to modify the Kozeny–Carman equation. It is shown that the fractal model has a good performance on the shape factor estimation, and value of the shape factor is largely controlled by porosity, pore area and tortuosity fractal dimensions of fluid occupied pores in hydrate-bearing sediments. Multiplying product of the shape factor, the squared specific surface area, and the squared hydraulic tortuosity linearly increases with increasing hydrate saturation in general for the pore-filling hydrate pore habit but linearly decreases due to the presence of grain-coating gas hydrates. This linear relation permits a feasible modification of the Kozeny–Carman equation for hydrate-bearing sediments, and values of the model parameter are suggested for pore-filling and grain-coating hydrate pore habits.
CONSTRUCTION OF SOME SPECIAL CONTINUOUS FUNCTIONS AND ANALYSIS OF THEIR FRACTIONAL INTEGRALS
Authors: KIM JINMYONG , KIM MYONGJIN
Published: July 2021

In this paper, we mainly construct two continuous functions defined on [Formula: see text] which have only one unbounded variation point, and show that both Box and Hausdorff dimensions of these functions are 1. We prove that their Riemann–Liouville fractional integrals are bounded variation function. We also show that these functions repair inaccuracies of the example in [N. Liu and K. Yao, Fractal dimension of a special continuous function, Fractals 26(4) (2018) 1850048; Y. S. Liang, Definition and classification of one-dimensional continuous functions with unbounded variation, Fractals 25(5) (2017) 1750048]. In the proofs, we mainly use Leibniz’s alternating series test and the properties of logarithmic function.
THE AVERAGE TRAPPING TIME WITH NON-NEAREST-NEIGHBOR JUMPS ON THE LEVEL-3 SIERPINSKI GASKET
Authors: CHEN YUN , ZHANG ZHIZHUO , WU BO
Published: July 2021

In this paper, we consider the trapping problem on the level-3 Sierpinski gasket [Formula: see text] when both nearest-neighbor (NN) and non-nearest-neighbor (NNN) jumps are included. Based on the topological structure of network and the method of probability generation function, we get the analytical expression of the average trapping time (ATT). Therefore, compared with the case where only NN jumps are allowed, we modify the specific value of ATT. Our results prove the exponent of the scaling expression has nothing to do with the NNN jump probability [Formula: see text], i.e. the scaling expression of ATT still scales superlinearly with the large network size. According to the analytical expression, we do numerical simulations of ATT with respect to parameters [Formula: see text] and [Formula: see text] (the number of generations of the network). The results show that the ATT will decrease with the increase of [Formula: see text]. These also indicate that NNN jump is helpful to improve the efficiency of random walk on network [Formula: see text].
Lp-Theory for the fractional time stochastic heat equation with an infinite-dimensional fractional Brownian motion
Authors: Han Jingqi , Yan Litan
Published: July 2021

In this paper, we study the [Formula: see text]-theory of the fractional time stochastic heat equation [Formula: see text] where [Formula: see text], [Formula: see text], [Formula: see text] denotes the Caputo derivative of order [Formula: see text], and [Formula: see text] is a sequence of i.i.d. fractional Brownian motions with a same Hurst index [Formula: see text]. The integral with respect to fractional Brownian motion is the Skorohod integral. By using the Malliavin calculus techniques and fractional calculus, we obtain a generalized Littlewood–Paley inequality, and prove the existence and uniqueness of [Formula: see text]-solution to such equation.
Existence of viscosity solutions with the optimal regularity of a two-peakon Hamilton–Jacobi equation
Authors: Cieślak Tomasz , Siemianowski Jakub
Published: July 2021

We study here a Hamilton–Jacobi equation with a quadratic and degenerate Hamiltonian, which comes from the dynamics of a multipeakon in the Camassa–Holm equation. It is given by a quadratic form with a singular positive semi-definite matrix. We increase the regularity of the value function considered in earlier works, which is known to be the viscosity solution. We prove that for a two-peakon Hamiltonian such solutions are actually [Formula: see text]-Hölder continuous in space and time-Lipschitz continuous. The time-Lipschitz regularity is proven in any dimension [Formula: see text]. Such a regularity is already known in the one-dimensional case and, moreover it is the best possible, as shown earlier.
Bending, Buckling and Vibration Analysis of Complete Microstructure-Dependent Functionally Graded Material Microbeams
Authors: Hong Jun , Wang Shaopeng , Zhang Gongye , Mi Changwen
Published: July 2021

A new functionally graded non-classical Timoshenko microbeam model is developed by using a variational formulation. The new model incorporates strain gradient, couple stress (rotation gradient) and velocity gradient effects and explains a power-law variation of two-phase materials through the thickness direction. The new model contains three additional material constants to account for the relative three gradient effects. The static bending, buckling and free vibration problems of the newly developed functionally graded material (FGM) beam are then analytically solved. Numerical results show that the differences between the prediction results of the current model and the classic model are significant when FGM beam thickness is very small, but they are diminishing as the thickness increases.
On the Probabilistic Convergence Spaces: Monad and its Eilenberg–Moore Category
Authors: Ahsanullah T. M. G. , Baran Tesnim Meryem , Al-Thukair Fawzi
Published: July 2021

Motivated by the category of probabilistic convergence spaces — a supercategory of the category of topological spaces; recently, we brought to light the categories of probabilistic convergence groups, probabilistic metric probabilistic convergence groups, probabilistic convergence transformation groups, along with their underpinning natural examples. The purpose of this paper is, first, to establish a result on the isomorphism between the categories of probabilistic metric groups, and probabilistic metric probabilistic convergence groups. Second, among others, we explore a monad in relation with probabilistic convergence groups, and probabilistic convergence spaces, and their related algebras. In so doing, we consider a product of the categories of probabilistic convergence groups and probabilistic convergence spaces in an attempt to construct a monad on it such that the corresponding category of algebras, the so-called Eilenberg–Moore category, is isomorphic to the category of probabilistic convergence transformation groups. Finally, invoking so-called Beck’s theorem on characterization of algebras, and starting with a particular adjunction, we achieve a monad. Conversely, given a monad, we obtain an adjunction which coincides with the original monad.
Performance of poly-o-phenylenediamine and its carbon dot composite electrode in the removal of Cu2+ from its aqueous solution
Authors: Meng Yu , Zhong Qing , Muslim Arzugul
Published: July 2021

Because −NH2and −NH− in poly-[Formula: see text]-phenylenediamine (P[Formula: see text]PD) can interact strongly with the empty orbitals of Cu to show unique electrochemical activity, P[Formula: see text]PD is suitable for the removal of Cu[Formula: see text] by electrochemical oxidation–reduction process. In this study, with P[Formula: see text]PD and its carbon dot composite (CDs/P[Formula: see text]PD) as working electrodes, the electrochemical reduction and removal of Cu[Formula: see text] in the aqueous solution were carried out with the potentiostatic method. According to effects of voltage, pH of the solution, initial concentration of Cu[Formula: see text], and electrochemical reduction time on the Cu[Formula: see text] removal, the Cu[Formula: see text] removal ratios of P[Formula: see text]PD and CDs/P[Formula: see text]PD were up to 64.69% and 73.34%, respectively, at −0.2 V and the optimal pH. Additionally, results showed that these processes were in line with the quasi-first order kinetic model. Both P[Formula: see text]PD and CDs/P[Formula: see text]PD showed good reproducibility in six cycles. After five times of repeated usage, the regeneration efficiencies of P[Formula: see text]PD and CDs/P[Formula: see text]PD dropped to 77.04% and 79.36%, respectively.
Overcoming the “Trump Trap”: How Thucydides Can Be Better Applied to US Policy on China
Authors: EASLEY Leif-Eric
Published: July 2021

Analogies to the Peloponnesian War have been misapplied in studies of US–China relations, especially regarding the so-called “Thucydides trap” of inevitable conflict between an established power and a rising power. This article addresses methodological problems with deriving policy lessons from political theory and ancient history. It then argues that Thucydides is more applicable to overcoming a pattern of leadership mistakes reminiscent of Athens’ populist politics, erosion of international agreements and mismanagement of alliances. To meet the China challenge, the United States must renew its national strength with good governance, productive interdependence, and sustained investment in human capital.
Chemical ordering and magnetic phase transitions in multiferroic BiFeO3–AFe1/2Sb1/2O3(A-Pb, Sr) solid solutions fabricated by a high-pressure synthesis
Authors: Raevskaya S. I. , Olekhnovich N. M. , Pushkarev A. V. , Radyush Y. V. , Kubrin S. P. , Titov V. V. , Artseva E. A. , Raevski I. P. , Zakharchenko I. N. , Chou C-C. , Malitskaya M. A.
Published: July 2021

Ceramic samples of BiFeO3-based perovskite solid solutions with the highly ordered complex perovskites [Formula: see text][Formula: see text]O3(PFS) and [Formula: see text][Formula: see text]O3 (SFS) were obtained using high-pressure synthesis at 4–6 GPa. Mössbauer studies revealed that BiFeO3-SFS compositions are characterized by a larger compositional inhomogeneity as compared to BiFeO3-PFS ones. In line with this result, concentration dependence of the magnetic phase transition temperature [Formula: see text] for BiFeO3-SFS compositions is close to the [Formula: see text] dependence for BiFeO3solid solution with disordered perovskite [Formula: see text][Formula: see text]O3(PFN). In contrast to this [Formula: see text] dependence for BiFeO3-PFS compositions nicely follows the theoretical [Formula: see text] dependence calculated for the case of the ordered distribution of Fe[Formula: see text] and non-magnetic Sb[Formula: see text] ions in the lattice (chemical ordering).
The role of subsidence and accommodation generation in controlling the nature of the aeolian stratigraphic record
Authors: Cosgrove Grace Isabel Emma , Colombera Luca , Mountney Nigel P.
Published: July 2021

Despite a well-documented record of preserved aeolian successions from sedimentary basins characterized by widely variable subsidence rates, the relationship between aeolian architecture and subsidence-driven accommodation generation remains poorly constrained and largely unquantified. Basin subsidence as a control on aeolian sedimentary architecture is examined through analysis of 55 ancient case-studies categorized into settings of ‘slow’ (>1–≤10 m Myr
−1
), ‘moderate’ (>10–≤100 m Myr
−1
) and ‘rapid’ (>100 m Myr
−1
) time-averaged subsidence rates. In rapidly subsiding basins, aeolian successions are thicker and associated with (1) thicker and more laterally extensive dune-sets with increased foreset preservation, (2) greater proportions of wet-type interdunes and surface stabilization features and (3) more extensive interdune migration surfaces, bounding sets that climb more steeply. In slowly subsiding basins, aeolian successions are thinner, and associated with a greater proportion of (1) aeolian sandsheets and (2) supersurfaces indicative of deflation and bypass. Rapid subsidence promotes (1) steeper bedform climb, resulting in increased preservation of the original dune foreset deposits and (2) relatively elevated water tables, leading to sequestration of deposits beneath the erosional baseline and encouraging development of stabilizing agents; both factors promote long-term preservation. Slow subsidence results in (1) lower angles of climb, associated with increased truncation of the original dune forms, and (2) greater post-depositional reworking, where sediment is exposed above the erosional baseline for extended time-periods. Quantitative analysis of sedimentary stratal architecture in relation to rates of basin subsidence helps constrain the mechanisms by which sedimentary successions are accumulated and preserved into the long-term stratigraphic record.

Supplementary material:
Results of statistical analyses presented here are available at
https://doi.org/10.6084/m9.figshare.c.5515695.v1
Toward a Competency-based Approach to Co-designing Technologies with People with Intellectual Disability
Authors: Bayor Andrew A. , Brereton Margot , Sitbon Laurianne , Ploderer Bernd , Bircanin Filip , Favre Benoit , Koplick Stewart
Published: July 2021

Ability-based design is a useful framework that centralizes the abilities (all that users can do) of people with disabilities in approaching the design of assistive technologies. However, although this framework aspires to support designing with people with all kinds of disabilities, it is mainly effective in supporting those whose abilities can be clearly defined and measured, in particular, physical and sensory attributes of ability. As a result, the ability-based design framework only provides limited guidance to design with users with intellectual disability, whose cognitive, physical, sensory, and practical abilities vary along a spectrum. In this article, we reflect on a long-term co-design study where we leveraged what we termed “competencies,” i.e., the representative practical skills people develop from their participation in life activities, in particular, mainstream technologies, such as social media and the Internet. Our reflection is based on our experience in designing SkillsTube, a web application we co-designed with young adults with intellectual disability to support them to learn life skills through videos. The app's design, which explored and leveraged their social media participation competencies, supported the fundamental participation of all participants and their peers. Their familiarity with the app's social media-inspired design features fostered confidence in their participation, usability, and engagement. Drawing on the findings and design process of the app, we discuss a
Competency-based
approach to designing with people with disabilities that extends upon ability-based design, by grounding it in user competencies.
Artificial Intelligence for Modeling Complex Systems: Taming the Complexity of Expert Models to Improve Decision Making
Authors: Gil Yolanda , Garijo Daniel , Khider Deborah , Knoblock Craig A. , Ratnakar Varun , Osorio Maximiliano , Vargas Hernán , Pham Minh , Pujara Jay , Shbita Basel , Vu Binh , Chiang Yao-Yi , Feldman Dan , Lin Yijun , Song Hayley , Kumar Vipin , Khandelwal Ankush , Steinbach Michael , Tayal Kshitij , Xu Shaoming , Pierce Suzanne A. , Pearson Lissa , Hardesty-Lewis Daniel , Deelman Ewa , Silva Rafael Ferreira Da , Mayani Rajiv , Kemanian Armen R. , Shi Yuning , Leonard Lorne , Peckham Scott , Stoica Maria , Cobourn Kelly , Zhang Zeya , Duffy Christopher , Shu Lele
Published: July 2021

Major societal and environmental challenges involve complex systems that have diverse multi-scale interacting processes. Consider, for example, how droughts and water reserves affect crop production and how agriculture and industrial needs affect water quality and availability. Preventive measures, such as delaying planting dates and adopting new agricultural practices in response to changing weather patterns, can reduce the damage caused by natural processes. Understanding how these natural and human processes affect one another allows forecasting the effects of undesirable situations and study interventions to take preventive measures. For many of these processes, there are expert models that incorporate state-of-the-art theories and knowledge to quantify a system's response to a diversity of conditions. A major challenge for efficient modeling is the diversity of modeling approaches across disciplines and the wide variety of data sources available only in formats that require complex conversions. Using expert models for particular problems requires integration of models with third-party data as well as integration of models across disciplines. Modelers face significant heterogeneity that requires resolving semantic, spatiotemporal, and execution mismatches, which are largely done by hand today and may take more than 2 years of effort.

We are developing a modeling framework that uses artificial intelligence (AI) techniques to reduce modeling effort while ensuring utility for decision making. Our work to date makes several innovative contributions: (1) an intelligent user interface that guides analysts to frame their modeling problem and assists them by suggesting relevant choices and automating steps along the way; (2) semantic metadata for models, including their modeling variables and constraints, that ensures model relevance and proper use for a given decision-making problem; and (3) semantic representations of datasets in terms of modeling variables that enable automated data selection and data transformations. This framework is implemented in the MINT (Model INTegration) framework, and currently includes data and models to analyze the interactions between natural and human systems involving climate, water availability, agricultural production, and markets. Our work to date demonstrates the utility of AI techniques to accelerate modeling to support decision-making and uncovers several challenging directions for future work.
Enhancing Internet Search Abilities for People with Intellectual Disabilities in Sri Lanka
Authors: Arachchi Theja K. , Sitbon Laurianne , Zhang Jinglan , Gamage Ruwan , Hewagamage Priyantha
Published: July 2021

This article presents how young adults with intellectual disability (ID) from Sri Lanka, who had not previously used the Internet, interacted with Google search while enhancing their web search abilities throughout three web search workshops. Considering the little attention paid to the learning needs of people with ID in the current offering of web search learning tools, we iteratively developed a suite of learning tools to support our participants when they need help in the web search workshops. We employed an iterative participatory approach, with observations and semi-structured interviews, to reflect on how to design eLearning tools that enhance the participants’ interactions with web search. The qualitative thematic analysis resulted in five distinct themes on strategies to support, build on, and develop the abilities of young adults with IDs as they engage with Google search in their native language: application of existing abilities, basic skills to match learning needs, conceptual understanding, animations to facilitate visual memory, and promoting active engagement. These themes will be a starting point for understanding participants’ learning needs and behavior on web search, which would be important for future research on learning support as well as on software design.
More than Privacy
Authors: Zhang Lefeng , Zhu Tianqing , Xiong Ping , Zhou Wanlei , Yu Philip S.
Published: July 2021

The vast majority of artificial intelligence solutions are founded on game theory, and differential privacy is emerging as perhaps the most rigorous and widely adopted privacy paradigm in the field. However, alongside all the advancements made in both these fields, there is not a single application that is not still vulnerable to privacy violations, security breaches, or manipulation by adversaries. Our understanding of the interactions between differential privacy and game theoretic solutions is limited. Hence, we undertook a comprehensive review of literature in the field, finding that differential privacy has several advantageous properties that can make more of a contribution to game theory than just privacy protection. It can also be used to build heuristic models for game-theoretic solutions, to avert strategic manipulations, and to quantify the cost of privacy protection. With a focus on mechanism design, the aim of this article is to provide a new perspective on the currently held impossibilities in game theory, potential avenues to circumvent those impossibilities, and opportunities to improve the performance of game-theoretic solutions with differentially private techniques.
Investigating Best Practices for Remote Summative Usability Testing with People with Mild to Moderate Dementia
Authors: Wood Rachel , Dixon Emma , Elsayed-Ali Salma , Shokeen Ekta , Lazar Amanda , Lazar Jonathan
Published: July 2021

People with dementia may miss out on the benefits of using technology, because they often find it difficult to use. Usability testing is one method to identify barriers and areas for improvement in technology. Unfortunately, usability testing is often not conducted with people with dementia, independent of their caregivers. Difficulty recruiting local participants with dementia who regularly use technology further compounds the problem. Remote methods have been proposed as one approach to recruiting hard-to-reach populations. Currently, it is unclear how to effectively conduct remote summative usability testing with people with dementia. We recruited 15 participants. Five took part in the pilot study and 10 participated in the main study. We identify best practices and make suggestions for remote summative usability tests with people who have mild to moderate dementia, independent of caregivers. We discuss our findings in three sections: (1) logistics for planning remote summative usability testing, (2) approaches for conducting remote summative usability testing, including modifications of research methods, and (3) considerations when evaluating findings from remote summative usability sessions. We also present modified usability testing methods we developed to meet the unique needs of users with mild to moderate dementia, and summarize lessons learned and new directions for research on this topic.
On Computing Multilinear Polynomials Using Multi-
r
-ic Depth Four Circuits
Authors: Chillara Suryajith
Published: July 2021

In this article, we are interested in understanding the complexity of computing multilinear polynomials using depth four circuits in which the polynomial computed at every node has a bound on the individual degree of
r
≥ 1 with respect to all its variables (referred to as multi-
r
-ic circuits). The goal of this study is to make progress towards proving superpolynomial lower bounds for general depth four circuits computing multilinear polynomials, by proving better bounds as the value of
r
increases.

Recently, Kayal, Saha and Tavenas (Theory of Computing, 2018) showed that any depth four arithmetic circuit of bounded individual degree
r
computing an explicit multilinear polynomial on
n

O
(1)

variables and degree
d
must have size at least (
n
/
r
1.1
)

Ω(√
d
/
r
)

. This bound, however, deteriorates as the value of
r
increases. It is a natural question to ask if we can prove a bound that does not deteriorate as the value of
r
increases, or a bound that holds for a
larger
regime of
r
.

In this article, we prove a lower bound that does not deteriorate with increasing values of
r
, albeit for a specific instance of
d
=
d
(
n
) but for a
wider
range of
r
. Formally, for all large enough integers
n
and a small constant η, we show that there exists an explicit polynomial on
n

O
(1)

variables and degree Θ (log
2
n
) such that any depth four circuit of bounded individual degree
r
≤
n
η must have size at least exp(Ω(log
2
n
)). This
improvement
is obtained by suitably adapting the complexity measure of Kayal et al. (Theory of Computing, 2018). This adaptation of the measure is inspired by the complexity measure used by Kayal et al. (SIAM J. Computing, 2017).
Can a Skywalker Localize the Midpoint of a Rope?
Authors: Monde Akihiro , Yamauchi Yukiko , Kijima Shuji , Masafumi Yamashita
Published: July 2021

This article poses a question about a simple localization problem. The question is if an
oblivious
walker on a line segment can localize the midpoint of the line segment in a
finite
number of steps observing the direction (i.e., Left or Right) and the distance to the nearest end point. This problem arises from
self-stabilizing
location problems by
autonomous mobile robots
with
limited visibility
, which is an abstract model attracting a wide interest in distributed computing. Contrary to appearances, it is far from trivial whether this simple problem is solvable, and it is not settled yet. This article is concerned with three variants of the problem with a minimal relaxation and presents self-stabilizing algorithms for them. We also show an easy impossibility theorem for bilaterally symmetric algorithms.