bluuebunny/crossref_metadata_2025 huggingface dataset:
Automatic Design of Dielectric Elastomer-Based Crawling Robots Using Shape and Topology Optimization
Authors: Chen Bicheng , Wang Nianfeng , Wang Rixin , Zhu Benliang , Zhang Xianmin , Sun Wenjie , Chen Wei
Published: May 2022

Dielectric elastomer-based crawling robots can utilize a voltage-induced deformation to achieve prescribed crawling movements. Although a rich repertoire of robots have been proposed with various design schemes, developing the logic and a unified methodology is hard. This work designs inchworm-inspired crawling robots based on computational optimization. An improved shape and topology optimization method is developed using a fat B-spline curve to generate a stable frame for the dielectric elastomer actuators (DEAs). An optimization framework is proposed, and the updating algorithm is assessed with a sensitivity analysis. The leg-DEA and abdomen-DEA of the crawling robot are modeled and designed automatically with iterations implemented in finite element simulation. An optimization soft crawling robot was fabricated and tested, which can move smoothly along the ground.
Twin peaks: The Omicron SARS-CoV-2 BA.1 and BA.2 epidemics in England
Authors: Elliott Paul , Eales Oliver , Steyn Nicholas , Tang David , Bodinier Barbara , Wang Haowei , Elliott Joshua , Whitaker Matthew , Atchison Christina , Diggle Peter J. , Page Andrew J. , Trotter Alexander J. , Ashby Deborah , Barclay Wendy , Taylor Graham , Ward Helen , Darzi Ara , Cooke Graham S. , Donnelly Christl A. , Chadeau-Hyam Marc
Published: May 2022

Rapid transmission of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant has led to record-breaking incidence rates around the world. The Real-time Assessment of Community Transmission-1 (REACT-1) study has tracked SARS-CoV-2 infection in England using reverse transcription polymerase chain reaction (RT-PCR) results from self-administered throat and nose swabs from randomly selected participants aged 5 years and older approximately monthly from May 2020 to March 2022. Weighted prevalence in March 2022 was the highest recorded in REACT-1 at 6.37% (
N
= 109,181), with the Omicron BA.2 variant largely replacing the BA.1 variant. Prevalence was increasing overall, with the greatest increase in those aged 65 to 74 years and 75 years and older. This was associated with increased hospitalizations and deaths, but at much lower levels than in previous waves against a backdrop of high levels of vaccination.
Genomic Basis of Occurrence of Cryptic Resistance among Oxacillin- and Cefoxitin-Susceptible
mecA
-Positive Staphylococcus aureus
Authors: Liang Bingshao , Xiong Zhile , Liang Zhuwei , Zhang Chao , Cai Hao , Long Yan , Gao Fei , Wang Jielin , Deng Qiulian , Zhong Huamin , Xie Yongqiang , Huang Lianfen , Gong Sitang , Zhou Zhenwen
Published: May 2022

The oxacillin- and cefoxitin-susceptible
mecA
-positive
Staphylococcus aureus
is a novel type of “stealth” methicillin-resistant
S. aureus
(MRSA), which is difficult to be detected using conventional methods. To investigate the genomic basis of their occurrence, we sequenced the whole genome of two previously recovered oxacillin- and cefoxitin-susceptible
mecA
-positive MRSA isolates from breast abscesses in a lactating woman and a nasal swab of a healthy student in Guangzhou.
Human Papillomavirus Minor Capsid Protein L2 Mediates Intracellular Trafficking into and Passage beyond the Endoplasmic Reticulum
Authors: Morante Anthony V. , Baboolal Daniel Davidnan , Simon Xavier , Pan Elizabeth/Mark Cheng-Ying , Meneses Patricio I.
Published: May 2022

High-risk types of human papillomaviruses (HPVs), such as HPV16, are highly associated with cervical, anogenital, and oropharyngeal cancers. The minor capsid protein L2 is essential for the intracellular trafficking of the viral DNA to the nucleus.
Early Eocene Diatoms and Silicoflagellates of the Cis-Donets Monocline (Russian Plate): Biostratigraphical and Paleogeographical Approaches
Authors: Oreshkina T. V.
Published: May 2022

The diatom assemblage of the Veshenskaya Formation studied in the borehole P-321 of the Cis-Donets monocline (southern part of the Russian Plate) is assigned to the lower Ypresian Moisseevia uralensis Zone. According to the available data, this zone corresponds to the Deflandrea oebisfeldensis and Dracodinium (=Wetzeliella) astra dinocyst zones and, accordingly, to the nanoplankton NP10 Zone. The presence of the zonal silicoflagellate species Naviculopsis foliacea confirms the Early Eocene age of the Veshenskaya Formation. The taxonomic similarity of diatoms and silicoflagellates of the region under consideration with silicofossil assemblages of Northern Europe suggests a stable link between these paleobasins at the beginning of the Early Eocene.
Health workforce supply, needs and financial feasibility in Lesotho: a labour market analysis
Authors: Asamani James Avoka , Zurn Pascal , Pitso Palesa , Mothebe Mathapelo , Moalosi Nthabiseng , Malieane Thabo , Bustamante Izquierdo Juana Paola , Zbelo Mesfin G , Hlabana Albert Mohlakola , Humuza James , Ahmat Adam , Okoroafor Sunny C , Nabyonga-Orem Juliet , Nyoni Jennifer
Published: May 2022

Background

The Government of Lesotho has prioritised health investment that aims to improve the health and socioeconomic development of the country, including the scaling up of the health workforce (HWF) training and improving their working conditions. Following a health labour market analysis, the paper highlights the available stock of health workers in Lesotho's health labour market, 10-year projected supply versus needs and the financial implications.

Methods

Multiple complementary approaches were used to collect data and analyse the HWF situation and labour market dynamics. These included a scooping assessment, desk review, triangulation of different data sources for descriptive analysis and modelling of the HWF supply, need and financial space.

Findings

Lesotho had about 20 942 active health workers across 18 health occupations in 2020, mostly community health workers (69%), nurses and midwives (17.9%), while medical practitioners were 2%. Almost one out of three professional nurses and midwives (28.43%) were unemployed, and nearly 20% of associate nurse professionals, 13.26% of pharmacy technicians and 24.91% of laboratory technicians were also unemployed. There were 20.73 doctors, nurses and midwives per 10 000 population in Lesotho, and this could potentially increase to a density of 31.49 doctors, nurses and midwives per 10 000 population by 2030 compared with a need of 46.72 per 10 000 population by 2030 based on projected health service needs using disease burden and evolving population size and demographics. The existing stock of health workers covered only 47% of the needs and could improve to 55% in 2030. The financial space for the HWF employment was roughly US$40.94 million in 2020, increasing to about US$66.69 million by 2030. In comparison, the cost of employing all health workers already in the supply pipeline (in addition to the currently employed ones) was estimated to be US$61.48 million but could reach US$104.24 million by 2030. Thus, a 33% gap is apparent between the financial space and what is required to guarantee employment for all health workers in the supply pipeline.

Conclusion

Lesotho’s HWF stock falls short of its population health need by 53%. The unemployment of some cadres is, however, apparent. Addressing the need requires increasing the HWF budget by at least 12.3% annually up to 2030 or prioritising at least 33% of its recurrent health expenditure to the HWF.
Implementation of a community-based referral project to improve access to emergency obstetric and newborn care in Rohingya population during COVID-19 pandemic in Bangladesh
Authors: Barua Mrittika , Saha Avijit , Chowdhury Srizan , Chowdhury Sayantan , Sajow Stenly Hely , Sarker Malabika
Published: May 2022

Introduction

The delay in seeking emergency obstetric care leads to significant maternal morbidity and mortality and can worsen during pandemics, especially in humanitarian conflict settings with low uptake of obstetric services. To mitigate the challenges related to the second delay caused by lack of transport in the COVID-19 pandemic, the organisation United Nations Population Fund implements a community-based referral project called Referral Hub in the Rohingya refugee population in Bangladesh. The objective of the paper is to describe the implementation process of the Referral hub and present clients’ utilisation and perception of the service.

Methods

Findings from part of a larger mixed-method study, the analysis of the standard operating protocol of the intervention, secondary data of routine utilisation of the 12 referral hubs between January and August 2020, 21 key informant interviews and a community survey among 100 pregnant women are presented in this paper.

Results

The findings show an increasing trend in the referral hub utilisation and a strong recommendation of the service.

Conclusion

Due to a robust referral mechanism by collaborating with the community and engaging accessible and free of cost transport service, the intervention has high potential to improve access to facility care in low-resource and humanitarian contexts, especially during pandemics.
Risk of venous thromboembolism in men with prostate cancer compared with men in the general population: a nationwide population-based cohort study in Sweden
Authors: Balabanova Yanina , Farahmand Bahman , Garmo Hans , Stattin Pär , Brobert Gunnar
Published: May 2022

Objective

To estimate the additional risk of venous thromboembolism (VTE) in men with prostate cancer compared with men without prostate cancer in Sweden.

Design

Nationwide cohort study following 92 105 men with prostate cancer and 466 241 men without prostate cancer (comparison cohort) matched 5:1 by birth year and residential region.

Setting

The male general population of Sweden (using the Nationwide Prostate Cancer data Base Sweden).

Primary and secondary outcome measures

Crude incidence proportion ratios (IPRs) comparing the incidence of VTE in men with prostate cancer and men in the comparison cohort. Cox regression was used to calculate HRs for VTE adjusted for confounders.

Results

2955 men with prostate cancer and 9774 men in the comparison cohort experienced a first VTE during a median of 4.5 years’ follow-up. Deep vein thrombosis (DVT) accounted for 52% of VTE cases in both cohorts. Median time from start of follow-up to VTE was 2.5 years (IQR 0.9–4.7) in the prostate cancer cohort and 2.9 years (IQR 1.3–5.0) in the comparison cohort. Crude incidence rates of VTE per 1000 person-years were 6.54 (95% CI 6.31 to 6.78) in the prostate cancer cohort (n=2955 events) and 4.27 (95% CI 4.18 to 4.35) in the comparison cohort (n=9774 events). The IPR decreased from 2.53 (95% CI 2.26 to 2.83) at 6 months to 1.59 (95% CI 1.52 to 1.67) at 5 years’ follow-up. Adjusted HRs were 1.48 (95% CI 1.39 to 1.57) for DVT and 1.47 (95% CI 1.39 to 1.56) for pulmonary embolism after adjustment for patient characteristics.

Conclusions

Swedish men with prostate cancer had a mean 50% increased risk of VTE during the 5 years following their cancer diagnosis compared with matched men free of prostate cancer. Physicians should be mindful of this marked increase in VTE risk in men with prostate cancer to help ensure timely diagnosis.
Making sense of phantom limb pain
Authors: Schone Hunter R , Baker Chris I , Katz Joel , Nikolajsen Lone , Limakatso Katleho , Flor Herta , Makin Tamar R
Published: May 2022

Phantom limb pain (PLP) impacts the majority of individuals who undergo limb amputation. The PLP experience is highly heterogenous in its quality, intensity, frequency and severity. This heterogeneity, combined with the low prevalence of amputation in the general population, has made it difficult to accumulate reliable data on PLP. Consequently, we lack consensus on PLP mechanisms, as well as effective treatment options. However, the wealth of new PLP research, over the past decade, provides a unique opportunity to re-evaluate some of the core assumptions underlying what we know about PLP and the rationale behind PLP treatments. The goal of this review is to help generate consensus in the field on how best to research PLP, from phenomenology to treatment. We highlight conceptual and methodological challenges in studying PLP, which have hindered progress on the topic and spawned disagreement in the field, and offer potential solutions to overcome these challenges. Our hope is that a constructive evaluation of the foundational knowledge underlying PLP research practices will enable more informed decisions when testing the efficacy of existing interventions and will guide the development of the next generation of PLP treatments.
Coating (Coating to Optimize Aneurysm Treatment in the New Flow Diverter Generation) study. The first randomized controlled trial evaluating a coated flow diverter (p64 MW HPC): study design
Authors: Pierot Laurent , Lamin Saleh , Barreau Xavier , Berlis Ansgar , Ciceri Elisa , Cohen José E , Costalat Vincent , Eker Omer F , Henkes Hans , Holtmannspötter Markus , Januel Anne-Christine , Keston Peter , Klisch Joachim , Psychogios Marios-Nikos , Valvassori Luca , Cognard Christophe , Spelle Laurent
Published: May 2022

Background

Due to its high efficacy, flow diversion is increasingly used in the management of unruptured and recanalized aneurysms. Because of the need for perioperative dual antiplatelet treatment (DAPT), flow diversion is not indicated for the treatment of ruptured aneurysms. To overcome this major limitation, surface modification—‘coating’—of flow diverters has been developed to reduce platelet aggregation on the implanted device, reduce thromboembolic complications, and facilitate the use of coated flow diverter treatment in patients with single antiplatelet treatment (SAPT). COATING (Coating to Optimize Aneurysm Treatment in the New Flow Diverter Generation) is a prospective, randomized, multicenter trial that aims to determine whether the use of the coated flow diverter p64 MW HPC under SAPT is non-inferior (or even superior) to the use of the bare flow diverter p64 MW under DAPT in relation to thromboembolic and hemorrhagic complications.

Methods

Patients with unruptured or recanalized aneurysms for which endovascular treatment with a flow diverter is indicated will be enrolled and randomly assigned on a 1:1 ratio to one of two treatment groups: p64 MW HPC with SAPT or p64 MW with DAPT.

Results

The primary endpoint is the number of diffusion-weighted imaging lesions visualized via MRI assessed within 48 hours (±24 hours) of the index procedure. Secondary primary endpoints are comparing safety and efficacy in both arms.

Conclusions

This randomized controlled trial is the first to directly compare safety and efficacy of coated flow diverters under SAPT with bare flow diverters under DAPT.

Trial registration number

http://clinicaltrials.gov/-NCT04870047.
Alternating current conductivity and superconducting properties of a holographic effective model with broken translations
Authors: Liu Yan , Wang Xi-Jing , Wu Jian-Pin , Zhang Xin
Published: May 2022

We construct a holographic effective superconducting theory by considering a special gauge-axion coupling. In the normal state, we observe that a peak emerges in the mid-IR in the AC conductivity for certain strength of broken translations and the gauge-axion coupling. It is attributed to the emergence of pseudo-Goldstone mode due to the competition of spontaneous symmetry breaking (SSB) and the explicit symmetry breaking (ESB). However, when the ESB dominates over the SSB, the peak disappears. In the superconducting phase, this gauge-axion coupling also plays a key role leading to a more evident gap at the low frequency conductivity. In addition, we also study the combined effects of the strength of broken translations and various couplings among the gauge field, axion fields and the complex scalar field.
Accuracy of one-dimensional approximation in neutron star quasi-normal modes
Authors: Sotani Hajime
Published: May 2022

Since the eigenfrequency of gravitational waves from cold neutron stars becomes a complex number, where the real and imaginary parts respectively correspond to an oscillation frequency and damping rate, one has to somehow solve the eigenvalue problem concerning the eigenvalue in two-dimensional parameter space. To avoid this bother, one sometimes adopts an approximation, where the eigenvalue is in one-dimensional parameter space. In this study, first, we show the accuracy of the zero-damping approximation, which is one of the one-dimensional approximations, for the fundamental and 1st pressure modes. But, this approximation is not applicable to the spacetime mode, because the damping rate of the spacetime mode is generally comparable to the oscillation frequency. Nevertheless, we find the empirical relation for the ratio of the imaginary part to the real part of the eigenfrequency, which is expressed as a function of the steller compactness almost independently of the adopted equations of state for neutron star matter. Adopting this empirical relation, one can express the eigenfrequency in terms of just the real part, i.e., the problem to solve becomes an eigenvalue problem with a one-dimensional eigenvalue. Then, we find that the frequencies are estimated with good accuracy even with such approximations even for the 1st spacetime mode.
XSS Armor: Constructing XSS Defensive Framework for Preserving Big Data Privacy in Internet-of-Things (IoT) Networks
Authors: Chaudhary Pooja , Gupta B. B. , Singh A. K.
Published: May 2022

Big data characterizes superfluity of voluminous data that may be in unstructured, structured and/or semi-structured format. Internet of Things networks emerged as one of the biggest sources of big data, stored at the cloud servers. Thereby, it inflates the threats of security attacks such as cross-site scripting (XSS) for stealing the sensitive information and violates the user’s privacy. It leverages an adversary to intervene into user’s individual space. Thus, in this paper, we propose an XSS defensive framework, named as Big IoT Data XSS Armor, to protect user’s privacy in IoT networks. It is a server-side framework that mitigates nonpersistent and persistent XSS attack. Former attack is detected by measuring the similarities in request and response URL with the XSS attack strings. To identify persistent XSS attack, the proposed framework operates by unveiling the irregularities between the genuine features and generated features. The experimental outcomes yield that this framework performs efficiently in shielding against XSS attack and surpasses the detection rate of other existing XSS thwarting techniques because it attains an accuracy of 98.9% and F-measure of 98.4%.
A fast cardiac electromechanics model coupling the Eikonal and the nonlinear mechanics equations
Authors: Stella Simone , Regazzoni Francesco , Vergara Christian , Dedé Luca , Quarteroni Alfio
Published: May 2022

We present a new model of human cardiac electromechanics for the left ventricle where electrophysiology is described by a Reaction–Eikonal model and which enables an off-line resolution of the reaction model, thus entailing a big saving of computational time. Subcellular dynamics is coupled with a model of tissue mechanics, which is in turn coupled with a Windkessel model for blood circulation. Our numerical results show that the proposed model is able to provide a physiological response to changes in certain variables (end-diastolic volume, total peripheral resistance, contractility). We also show that our model is able to reproduce with high accuracy and with a considerably lower computational time the results that we would obtain if the monodomain model should be used in place of the Eikonal model.
Extended decoupled anisotropic solutions in f(ℛ,𝒯 ,ℛγχ𝒯γχ) gravity
Authors: Sharif M. , Naseer Tayyab
Published: May 2022

In this paper, we consider static spherical structure to develop some anisotropic solutions by employing the extended gravitational decoupling scheme in the background of [Formula: see text] gravity, where [Formula: see text] and [Formula: see text] indicate the Ricci scalar and trace of the energy–momentum tensor, respectively. We transform both radial as well as temporal metric functions and apply them on the field equations that produce two different sets corresponding to the decoupling parameter [Formula: see text]. The first set is associated with isotropic distribution, i.e. modified Krori–Barua solution. The second set is influenced from anisotropic factor and contains unknowns which are determined by taking some constraints. The impact of decoupling parameter is then analyzed on the obtained physical variables and anisotropy. We also investigate energy conditions and some other parameters such as mass, compactness and redshift graphically. It is found that our solution corresponding to pressure-like constraint shows stable behavior throughout in this gravity for the considered range of [Formula: see text].
Refined swampland conjecture in deformed Starobinsky gravity
Authors: Channuie Phongpichit
Published: May 2022

In order to validate or invalidate a large class of low energy effective theories, the swampland conjecture has attracted significant attention recently. It can be stated as inequalities on the potential of a scalar field which is conjectured to satisfy certain constraints. In this work, we discuss the theoretical viability of deformed Starobinsky gravity in light of the refined swampland conjectures. We consider the deformation of the form [Formula: see text] with [Formula: see text] being a constant. We then constrain [Formula: see text] using the spectral index of curvature perturbation [Formula: see text] and the tensor-to-scalar ratio [Formula: see text]. We demonstrate that the model under consideration is in strong tension with the refined swampland conjecture. However, regarding our analysis with proper choices of parameters [Formula: see text] and [Formula: see text], we discover that the model can always satisfy this new refined swampland conjecture. Therefore, the model might be in “landscape” since the “further refining de Sitter swampland conjecture” is satisfied.
Evaluation of string comparators for record linkage in Chinese environment
Authors: Guo Heng , Li Yalin , Liu Ying , Li Weifu , Li Xinran
Published: May 2022

In Chinese record linkage, the similarity measurement of short text fields such as identifying information has an important influence on the effect of linkage. In this paper, we compared the performance of six different string comparators for Chinese record linkage, including Hamming, Levenshtein, Jaro, Overlap Coefficient, Cosine and Ratcliff–Obershelp similarity. At the same time, the expectation-maximization algorithm was used to perform the probabilistic record linkage. The results showed that compared with other string comparators, Jaro similarity not only gets higher precision and recall, but also has the least computational time. All in all, this comparator can be used if we focus on string spelling and pronunciation without considering semantic similarity.
Nanoarchitectonics of Sn3O4/g-C3N4 Heterostructure Materials for Better Photocatalytic and Electrochemical Performance
Authors: Hu Wenquan , Song Jia , Wang Ming
Published: May 2022

Sn3O4/g-C3N4 heterostructure nanomaterials were prepared by calcining melamine and the hydrothermal method. The microstructure and morphology of the synthesized specimen were characterized by X-ray diffraction (XRD), electron microscope (SEM and TEM) and nitrogen adsorption and desorption (BET). The photocatalytic activity was evaluated by the photodegradation of methylene blue (MB) under visible light irradiation and the electrochemical performance was tested under a typical three-electrode configuration. The results show that the Sn3O4/g-C3N4 heterojunctions exhibit more superior photocatalytic performance for degrading MB compared with single Sn3O4 and g-C3N4. The degradation rate of MB reaches up to a maximal 90.30% within 75[Formula: see text]min, which is far higher than that of Sn3O4 (61.30%). It is attributed to the effective interfacial contact between Sn3O4 and g-C3N4, which increases charge transfer and prolongs electron-hole separation time. The specific capacitance of Sn3O4/g-C3N4 is 28.6% higher than that of Sn3O4 due to the formation of a heterostructure.
About this title - The Great Ordovician Biodiversification Event: Insights from the Tafilalt Biota, Morocco
Authors: Hunter A. W. , Álvaro J. J. , Lefebvre B. , Van Roy P. , Zamora S.
Published: May 2022

About 40 million years after the Cambrian Explosion, the Great Ordovician Biodiversification Event (GOBE) represents a second and dramatic burst in marine biodiversity, with major changes in the structure of ecosystems and the progressive replacement of the distinctive Cambrian Evolutionary Fauna by the Paleozoic Evolutionary Fauna. However, the GOBE is not a single, worldwide, short-term event, but rather the complex sum of successive diversifications occurring in distinct taxonomic groups, trophic guilds and regions. This book focuses on the Late Ordovician Tafilalt Biota, Anti-Atlas Morocco, which provides a snapshot of the GOBE in high-latitude regions of the Southern Hemisphere. A series of contributions explore different aspects of the Tafilalt Biota, including its geological setting, the international fossil trade in this area and a series of detailed systematic contributions describing many new taxa of marine invertebrates. This volume represents a significant contribution to the understanding of the Tafilalt Biota and its significance to the GOBE.
Subaerial volcaniclastic deposits – influences of initiation mechanisms and transport behaviour on characteristics and distributions
Authors: Major Jon J.
Published: May 2022

Subaerial volcaniclastic deposits are produced principally by volcanic debris avalanches, pyroclastic density currents, lahars, and tephra falls. Those deposits have widely ranging geomorphic and sedimentologic characteristics; they can mantle, modify, or create new topography, and their emplacement and subsequent reworking can have an outsized impact on the geomorphic and sedimentologic responses of watersheds surrounding, and channels draining, volcanoes. Volcaniclastic deposits provide a wealth of information about eruptive histories, volcanic processes, and landscape responses to eruptions. The volcanic processes that produce these deposits, and consequently the character and sedimentary structures of the deposits themselves, are influenced by initiation mechanism. Deposit preservation is affected by deposit magnitude, texture, and composition, depositional environment, and climate regime. Innovative analyses of deposits from several modern eruptions and advancements in physical and numerical modelling have vastly improved our understanding of volcanic processes, interpretations of eruptive histories, and recognition of the hazards posed by volcanic eruptions. This contribution highlights and summarizes major advances that have occurred in the past few decades in understanding of volcaniclastic deposits and linkages with volcanic processes.
Chatbots to Support Young Adults’ Mental Health: An Exploratory Study of Acceptability
Authors: Koulouri Theodora , Macredie Robert D. , Olakitan David
Published: May 2022

Despite the prevalence of mental health conditions, stigma, lack of awareness, and limited resources impede access to care, creating a need to improve mental health support. The recent surge in scientific and commercial interest in conversational agents and their potential to improve diagnosis and treatment seems a potentially fruitful area in this respect, particularly for young adults who widely use such systems in other contexts. Yet, there is little research that considers the acceptability of conversational agents in mental health. This study, therefore, presents three research activities that explore whether conversational agents and, in particular, chatbots can be an acceptable solution in mental healthcare for young adults. First, a survey of young adults (in a university setting) provides an understanding of the landscape of mental health in this age group and of their views around mental health technology, including chatbots. Second, a literature review synthesises current evidence relating to the acceptability of mental health conversational agents and points to future research priorities. Third, interviews with counsellors who work with young adults, supported by a chatbot prototype and user-centred design techniques, reveal the perceived benefits and potential roles of mental health chatbots from the perspective of mental health professionals, while suggesting preconditions for the acceptability of the technology. Taken together, these research activities: provide evidence that chatbots are an acceptable solution to offering mental health support for young adults; identify specific challenges relating to both the technology and environment; and argue for the application of user-centred approaches during development of mental health chatbots and more systematic and rigorous evaluations of the resulting solutions.
Combining Filtering and Cross-Correlation Efficiently for Streaming Time Series
Authors: Zhong Sheng , Souza Vinicius M. A. , Mueen Abdullah
Published: May 2022

Monitoring systems have hundreds or thousands of distributed sensors gathering and transmitting real-time streaming data. The early detection of events in these systems, such as an earthquake in a seismic monitoring system, is the base for essential tasks as warning generations. To detect such events is usual to compute pairwise correlation across the disparate signals generated by the sensors. Since the data sources (e.g., sensors) are spatially separated, it is essential to consider the lagged correlation between the signals. Besides, many applications require to process a specific band of frequencies depending on the event’s type, demanding a pre-processing step of filtering before computing correlations. Due to the high speed of data generation and a large number of sensors in these systems, the operations of filtering and lagged cross-correlation need to be efficient to provide real-time responses without data losses. This article proposes a technique named FilCorr that efficiently computes both operations in one single step. We achieve an order of magnitude speedup by maintaining frequency transforms over sliding windows. Our method is exact, devoid of sensitive parameters, and easily parallelizable. Besides our algorithm, we also provide a publicly available real-time system named Seisviz that employs FilCorr in its core mechanism for monitoring a seismometer network. We demonstrate that our technique is suitable for several monitoring applications as seismic signal monitoring, motion monitoring, and neural activity monitoring.
File Packing from the Malware Perspective: Techniques, Analysis Approaches, and Directions for Enhancements
Authors: Muralidharan Trivikram , Cohen Aviad , Gerson Noa , Nissim Nir
Published: May 2022

With the growing sophistication of malware, the need to devise improved malware detection schemes is crucial. The packing of executable files, which is one of the most common techniques for code protection, has been repurposed for code obfuscation by malware authors as a means of evading malware detectors (mainly static analysis-based detectors). This paper provides statistics on the use of packers based on an extensive analysis of 24,000 PE files (both malicious and benign files) for the past 10 years, which allowed us to observe trends in packing use during that time and showed that packing is still widely used in malware. This paper then surveys 23 methods proposed in academic research for the detection and classification of packed
portable executable (PE)
files and highlights various trends in malware packing. The paper highlights the differences between the methods and their abilities to detect and identify various aspects of packing. A taxonomy is presented, classifying the methods as static, dynamic, and hybrid analysis-based methods. The paper also sheds light on the increasing role of machine learning methods in the development of modern packing detection methods. We analyzed and mapped the different packing methods and identified which of them can be countered by the detection methods surveyed in this paper.
Feedback-Directed Metamorphic Testing
Authors: Sun Chang-Ai , Dai Hepeng , Liu Huai , Chen Tsong Yueh
Published: May 2022

Over the past decade, metamorphic testing has gained rapidly increasing attention from both academia and industry, particularly thanks to its high efficacy on revealing real-life software faults in a wide variety of application domains. On the basis of a set of metamorphic relations among multiple software inputs and their expected outputs, metamorphic testing not only provides a test case generation strategy by constructing new (or follow-up) test cases from some original (or source) test cases, but also a test result verification mechanism through checking the relationship between the outputs of source and follow-up test cases. Many efforts have been made to further improve the cost-effectiveness of metamorphic testing from different perspectives. Some studies attempted to identify “good” metamorphic relations, while other studies were focused on applying effective test case generation strategies especially for source test cases. In this article, we propose improving the cost-effectiveness of metamorphic testing by leveraging the feedback information obtained in the test execution process. Consequently, we develop a new approach, namely feedback-directed metamorphic testing, which makes use of test execution information to dynamically adjust the selection of metamorphic relations and selection of source test cases. We conduct an empirical study to evaluate the proposed approach based on four laboratory programs, one GNU program, and one industry program. The empirical results show that feedback-directed metamorphic testing can use fewer test cases and take less time than the traditional metamorphic testing for detecting the same number of faults. It is clearly demonstrated that the use of feedback information about test execution does help enhance the cost-effectiveness of metamorphic testing. Our work provides a new perspective to improve the efficacy and applicability of metamorphic testing as well as many other software testing techniques.
Single and Multi-objective Test Cases Prioritization for Self-driving Cars in Virtual Environments
Authors: Birchler Christian , Khatiri Sajad , Derakhshanfar Pouria , Panichella Sebastiano , Panichella Annibale
Published: May 2022

Testing with simulation environments helps to identify critical failing scenarios for self-driving cars (SDCs). Simulation-based tests are safer than in-field operational tests and allow detecting software defects before deployment. However, these tests are very expensive and are too many to be run frequently within limited time constraints.

In this article, we investigate test case prioritization techniques to increase the ability to detect SDC regression faults with virtual tests earlier. Our approach, called
SDC-Prioritizer
, prioritizes virtual tests for SDCs according to static features of the roads we designed to be used within the driving scenarios. These features can be collected without running the tests, which means that they do not require past execution results. We introduce two evolutionary approaches to prioritize the test cases using diversity metrics (black-box heuristics) computed on these static features. These two approaches, called
SO-SDC-Prioritizer
and
MO-SDC-Prioritizer
, use single-objective and multi-objective
genetic algorithms
(
GA
), respectively, to find trade-offs between executing the less expensive tests and the most diverse test cases earlier.

Our empirical study conducted in the SDC domain shows that
MO-SDC-Prioritizer
significantly (
P
- value <=0.1
e
-10) improves the ability to detect safety-critical failures at the same level of execution time compared to baselines: random and greedy-based test case orderings. Besides, our study indicates that multi-objective meta-heuristics outperform single-objective approaches when prioritizing simulation-based tests for SDCs.

MO-SDC-Prioritizer
prioritizes test cases with a large improvement in fault detection while its overhead (up to 0.45% of the test execution cost) is negligible.
Graded Refinement, Retrenchment, and Simulation
Authors: Banach Richard
Published: May 2022

Refinement of formal system models towards implementation has been a mainstay of system development since the inception of formal and Correct by Construction approaches to system development. However, pure refinement approaches do not always deal fluently with all desirable system requirements. This prompted the development of alternatives and generalizations, such as retrenchment. The crucial concept of simulation is key to judging the quality of the conformance between abstract and more concrete system models. Reformulations of these theoretical approaches are reprised and are embedded in a graded framework. The added flexibility this offers is intended to deal more effectively with the needs of applications in which the relationship between different levels of abstraction is not straightforward, and in which behavior can oscillate between conforming quite closely to an idealized abstraction and deviating quite far from it. The framework developed is confronted with an intentionally demanding case study: a model active control system for the protection of buildings during earthquakes. This offers many challenges: it is hybrid/cyber-physical; it has to respond to rather unpredictable inputs; and it has to straddle the gap between continuous behavior and discretized/quantized/numerical implementation.
Machine Learning–based Modeling and Prediction of the Intrinsic Relationship between Human Emotion and Music
Authors: Su Jun , Zhou Peng
Published: May 2022

Human emotion is one of the most complex psychophysiological phenomena and has been reported to be affected significantly by music listening. It is supposed that there is an intrinsic relationship between human emotion and music, which can be modeled and predicted quantitatively in a supervised manner. Here, a heuristic clustering analysis is carried out on large-scale free music archive to derive a genre-diverse music library, to which the emotional response of participants is measured using a standard protocol, consequently resulting in a systematic emotion-to-music profile. Eight machine learning methods are employed to statistically correlate the basic sound features of music audio tracks in the library with the measured emotional response of tested people to the music tracks in a training set and to blindly predict the emotional response from sound features in a test set.

This study found that nonlinear methods are more robust and predictable but considerably more time-consuming than linear approaches. The neural networks have strong internal fittability but are associated with a significant overfitting issue. The support vector machine and Gaussian process exhibit both high internal stability and satisfactory external predictability in all used methods; they are considered as promising tools to model, predict, and explain the intrinsic relationship between human emotion and music. The psychological basis and perceptional implication underlying the built machine learning models are also discussed to find out the key music factors that affect human emotion.
A Human Factors Approach to Validating Driver Models for Interaction-aware Automated Vehicles
Authors: Siebinga Olger , Zgonnikov Arkady , Abbink David
Published: May 2022

A major challenge for autonomous vehicles is interacting with other traffic participants safely and smoothly. A promising approach to handle such traffic interactions is equipping autonomous vehicles with interaction-aware controllers (IACs). These controllers predict how surrounding human drivers will respond to the autonomous vehicle’s actions, based on a driver model. However, the predictive validity of driver models used in IACs is rarely validated, which can limit the interactive capabilities of IACs outside the simple simulated environments in which they are demonstrated. In this article, we argue that besides evaluating the interactive capabilities of IACs, their underlying driver models should be validated on natural human driving behavior. We propose a workflow for this validation that includes scenario-based data extraction and a two-stage (tactical/operational) evaluation procedure based on human factors literature. We demonstrate this workflow in a case study on an inverse-reinforcement-learning-based driver model replicated from an existing IAC. This model only showed the correct tactical behavior in 40% of the predictions. The model’s operational behavior was inconsistent with observed human behavior. The case study illustrates that a principled evaluation workflow is useful and needed. We believe that our workflow will support the development of appropriate driver models for future automated vehicles.
Difluorophosphoric Acid Generation and Crossover Reactions in LiNixCoyMnzO2 Cathodes Operating at High Voltage
Authors: Jayawardana Chamithri , Rodrigo Nuwanthi D. , Rynearson Leah , Lucht Brett L.
Published: May 2022

Cycling lithiated metal oxides to high potential (>4.5 V vs Li) is of significant interest for the next generation of lithium ion batteries as this significantly increases the capacity and energy of cells. However, cells cycled to high potential suffer from rapid capacity fade due to a combination of thickening of the anode solid electrolyte interphase (SEI) and impedance growth on the cathode. While transition metal catalysed degradation of the anode SEI has been widely proposed as a primary source of capacity loss, a related acid induced degradation of the anode SEI is proposed. A systematic investigation of LiNi0.5Co0.2Mn0.3O2, and LiNi0.8Co0.1Mn0.1O2 cathodes cycled to 4.2 and 4.6 V has been conducted and the oxidative generation of the strong acid difluorophosphoric acid (F2PO2H) has been quantified by solution Nuclear Magnetic Resonance (NMR) spectroscopy. Ex-situ surface analysis of the electrodes with X-ray Photo Electron spectroscopy (XPS) suggests that the generation of F2PO2H correlates with a thickening of the anode SEI and an increase in the fluorophosphate content of the SEI. Changes to the LiNi0.8Co0.1Mn0.1O2 surface for cells cycled to 4.6 V are also consistent with the generation of acidic species. There is good correlation between the concentration F2PO2H, anode SEI degradation and the capacity loss of the cells.
Single-cell RNA sequencing and binary hierarchical clustering define lung interstitial macrophage heterogeneity in response to hypoxia
Authors: Campbell Nzali V. , Mickael Claudia , Kumar Sushil , Zhang Hui , Campbell Ian L. , Gillen Austin E. , Trentin Caio O. , Diener Katrina , Gao Bifeng , Kheyfets Vitaly O. , Gu Sue , Kumar Rahul , Phang Tzu , Brown R. Dale , Graham Brian B. , Stenmark Kurt R.
Published: May 2022

Few studies have examined lung interstitial macrophage (IM) molecular phenotypes after being exposed to hypoxia in vivo at the single-cell level, even though macrophages contribute to hypoxic pulmonary hypertension (PH). We aimed to determine IM diversity and its association with hypoxia-induced PH. We hypothesized that integrating single-cell RNA sequencing (scRNAseq) and binary hierarchal clustering (BHC) could resolve IM heterogeneity under normal homeostatic conditions and changes induced by hypoxia exposure. Cx3cr1GFP/+ reporter mice were exposed to normoxic conditions (∼21% [Formula: see text]) or exposed to 1 day ( D1) or 7 days ( D7) of hypoxia (∼10% [Formula: see text]). We used flow cytometry to isolate Cx3cr1+ IMs and the 10X Genomics platform for scRNAseq, Cell Ranger, Seurat, ClusterMap, monocle, ingenuity pathway analysis, and Fisher’s exact test ( q value < 0.05) for functional investigations. n = 374 (normoxia), n = 2,526 ( D1), and n = 1,211 ( D7) IMs were included in the analyses. We identified three normoxia-related cell types, five hypoxia-associated cell types that emerged at D1, and three that appeared at D7. We describe the existence of a putative resident trained innate IM, which is present in normoxia, transiently depleted at D1, and recovered after 7 days of sustained hypoxia. We also define a rare putative pathogenic population associated with transcripts implicated in PH development that emerges at D7. In closing, we describe the successful integration of BHC with scRNAseq to determine IM heterogeneity and its association with PH. These results shed light on how resident-trained innate IMs become more heterogeneous but ultimately accustomed to hypoxia.
Gene and protein expression of dorsal root ganglion sensory receptors in normotensive and hypertensive male rats
Authors: Weavil Joshua C. , Kwon Oh Sung , Hughen Ronald W. , Zhang Jie , Light Alan R. , Amann Markus
Published: May 2022

The exercise pressor reflex (EPR), a neurocirculatory control mechanism, is exaggerated in hypertensive humans and rats. Disease-related abnormalities within the afferent arm of the reflex loop, including mechano- and metabosensitive receptors located at the terminal end of group III/IV muscle afferents, may contribute to the dysfunctional EPR in hypertension. Using control (WKY) and spontaneous hypertensive (SHR) rats, we examined dorsal root ganglion (DRG) gene and protein expression of molecular receptors recognized as significant determinants of the EPR. Twelve lumbar DRGs (6 left, 6 right) were harvested from each of 10 WKY [arterial blood pressure (MAP): 96 ± 9 mmHg] and 10 SHR (MAP: 144 ± 9 mmHg). DRGs from the left side were used for protein expression (Western blotting; normalized to GAPDH), whereas right-side DRGs (i.e., parallel structure) were used to determine mRNA levels (RNA-sequencing, normalized to TPM). Analyses focused on metabosensitive (ASIC3, Bradykinin receptor B2, EP4, P2X3, TRPv1) and mechanosensitive (Piezo1/2) receptors. Although Piezo1 was similar in both groups ( P = 0.75), protein expression for all other receptors was significantly higher in SHR compared with WKY. With the exception of a greater Bradykinin-receptor B2 in SHR ( P < 0.05), mRNA expression of all other receptors was not different between groups ( P > 0.18). The higher protein content of these sensory receptors in SHR indirectly supports the previously proposed hypothesis that the exaggerated EPR in hypertension is, in part, due to disease-related abnormalities within the afferent arm of the reflex loop. The upregulated receptor content, combined with normal mRNA levels, insinuates that posttranscriptional regulation of sensory receptor protein expression might be impaired in hypertension.
The influence of experimental low back pain on neural networks involved in the control of lumbar erector spinae muscles
Authors: Rohel Antoine , Desmons Mikaël , Léonard Guillaume , Desgagnés Amélie , da Silva Rubens , Simoneau Martin , Mercier Catherine , Massé-Alarie Hugo
Published: May 2022

In the presence of experimental low back pain, spinal, subcortical, and cortical motor networks involved in the control of back muscles were not modified. However, once the pain disappeared, a reduction in motoneuronal excitability was observed without change in corticospinal and vestibulospinal excitability, suggesting a reduction in descending drive. Experimental low back pain may elicit long-term plasticity even after pain extinction.