bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lightweight mechanical metamaterials designed using hierarchical truss elements
Authors: Mizzi Luke , Spaggiari Andrea 
Published: July 2020

Abstract
Rotating unit systems constitute one of the main classes of auxetic metamaterials. In this work, a new design procedure for lightweight auxetic systems based on this deformation mechanism is proposed through the implementation of a hierarchical triangular truss network in place of a full block of material for the rotating component of the system. Using numerical simulations in conjunction with experimental tests on 3D printed prototypes, the mechanical properties of six types of auxetic structures, which include a range of rotating polygons and chiral honeycombs, were analysed under the application of small tensile loads. The results obtained show that there is almost no difference in the Poisson’s ratios obtained from the regular, full structures and the ones made from triangular truss systems despite the latter, in some cases, being 80% lighter than the former. This indicates that these systems could be ideal candidates for implementation in applications requiring lightweight auxetic metamaterial systems such as in the aerospace industry.
Object classification based on piezoelectric actuator-sensor pair on robot hand using neural network
Authors: Chung Jaehoon , Lim Hyeonjung , Lim Myotaeg , Cha Youngsu 
Published: July 2020

Abstract
We propose a piezoelectric actuator-sensor pair applicable to object classification, which comprises two piezoelectric films on a polyethylene terephthalate substrate layer. One piezoelectric film is used as an actuator, and another as a sensor. The actuator-sensor pair is installed on a robot hand, and a neural network classifier is used to conduct object classification. Sensor data for learning process are acquired when the actuator is oscillating, while the robot hand grasps objects. Specifically, a sinusoidal input voltage with frequency sweep is supplied to the actuator, and the sensor outputs the signal transferred from the actuator simultaneously. The obtained data undergoes a series of preprocessing procedures to be used as data input for learning. Several neural network classifier models are trained with the preprocessed dataset, and the most suitable model is selected as our classifier. Our classifier successfully predicted the object data in the test set. Furthermore, we develop a real-time recognition system and demonstrate the feasibility of the actuator-sensor pair.
Analytical model of 2D electric potential and current transfer in superconducting tapes with a current flow diverter architecture
Authors: Fournier-Lupien Jean-Hughes , Del Vecchio Patrick , Lacroix Christian , Sirois Frédéric 
Published: July 2020

Abstract
This work presents a generalization of the concept of current transfer length (CTL) between the stabilizer and the superconducting layer of high temperature superconductor (HTS) coated conductor tapes with a current flow diverter (CFD) architecture. The CFD architecture consists in a non-uniform interfacial resistance between the two layers, namely a high interfacial resistance in the middle of the tape and a low interfacial resistance on its sides. With this architecture, when the current transfers from the stabilizer to the superconductor to circumvent a normal zone or a crack, a current density component along the width of the tape appears, required for the current to circumvent the high interfacial resistance. This current component does not exist in a classical tape architecture. To describe quantitatively this current transfer, we developed a quasi-analytical formula that computes the electric potential in the stabilization layer, from which we can derive the current density components. The model is then used to determine the current transfer length (CTL) in tapes with a CFD architecture, using a generalized definition of the CTL. The model is simple and quick to run and allows deepening our understanding of the dependence of the CTL with different geometric and materials parameters, and clearly shows that the CFD architecture is very effective in increasing the CTL of HTS tapes while keeping the effective interfacial resistance to very low values. The model is quasi-analytical because it requires the numerical evaluation of a transcendental equation for determining one set of coefficients, but otherwise, it takes the form of a double summation of analytical functions (series solution). The exactness of the model has been verified by comparisons with finite element simulations.
Coherent dynamics in frustrated coupled parametric oscillators
Authors: Calvanese Strinati Marcello , Aharonovich Igal , Ben-Ami Shai , Dalla Torre Emanuele G , Bello Leon , Pe’er Avi 
Published: July 2020

Abstract
We explore the coherent dynamics in a small network of three coupled parametric oscillators and demonstrate the effect of frustration on the persistent beating between them. Since a single-mode parametric oscillator represents an analogue of a classical Ising spin, networks of coupled parametric oscillators are considered as simulators of Ising spin models, aiming to efficiently calculate the ground state of an Ising network—a computationally hard problem. However, the coherent dynamics of coupled parametric oscillators can be considerably richer than that of Ising spins, depending on the nature of the coupling between them (energy preserving or dissipative), as was recently shown for two coupled parametric oscillators. In particular, when the energy-preserving coupling is dominant, the system displays everlasting coherent beats, transcending the Ising description. Here, we extend these findings to three coupled parametric oscillators, focussing in particular on the effect of frustration of the dissipative coupling. We theoretically analyse the dynamics using coupled nonlinear Mathieu’s equations, and corroborate our theoretical findings by a numerical simulation that closely mimics the dynamics of the system in an actual experiment. Our main finding is that frustration drastically modifies the dynamics. While in the absence of frustration the system is analogous to the two-oscillator case, frustration reverses the role of the coupling completely, and beats are found for small energy-preserving couplings.
Resonant photocurrent from a single quantum emitter in tungsten diselenide
Authors: Paur Matthias , Molina-Mendoza Aday J , Polyushkin Dmitry , Michaelis de Vasconcellos Steffen , Bratschitsch Rudolf , Mueller Thomas 
Published: July 2020

Abstract
Single quantum emitters (SQEs) are the basic building blocks for quantum optics and quantum information technology. Strain-induced defects in monolayer transition metal dichalcogenides (TMDs) have been shown to be a promising platform for the generation of SQEs. In particular, achieving optically active and electrically controlled quantum emitters make these materials attractive for applications ranging from quantum communication and optoelectronics to high resolution metrology. Here, we report the spectral photoresponse of monolayer WSe2 upon strain, where we observe a connection between single-photon emission and photocurrent (PC) generation in a p-n device. A strong antibunching in second-order correlation from this localized emitter unambiguously demonstrates the single-photon nature of the emission, whereas the PC is highly dominated by the absorption at such a localized state, showing an exponential dependence with the applied electric field. Furthermore, we can resolve narrow PC peaks with 1.0 meV spectral width.
Atomic layer deposition of TiO2 and Al2O3 thin films for the electrochemical study of corrosion protection in aluminum alloy cans used in beverage
Authors: Dias V M , Chiappim W , Fraga M A , Maciel H S , Marciano F R , Pessoa R S 
Published: July 2020

Abstract
Titanium dioxide (TiO2) and aluminum oxide (Al2O3) thin films, with thicknesses around 100 nm, were grown on commercial pure- and resin-coated Al substrates using the atomic layer deposition (ALD). A comprehensive and comparative study of corrosion protection was carried out by linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) measurements for a set of six samples: two reference samples (Al-bare and Al-resin), and four ALD coated samples ( Al-TiO2, Al-Al2O3, Al-resin-TiO2, and Al-resin-Al2O3). The LSV and EIS results display good mutual agreement, indicating a higher protection efficiency of all ALD-coated samples after immersion in NaCl. When compared to Al-bare, all ALD coated samples (TiO2 or Al2O3) showed a corrosion inhibition enhancement factor of 99%. Besides, our results demonstrated that Al-resin+Al2O3 has 24.95% and 33.40% more corrosion inhibition than Al-Al2O3 and Al-resin, respectively. EIS data were fitted by an equivalent electric circuit (EEC). The Nyquist and Bode plots from the experiments showed that ALD films are a potential candidate for altering/improving commercial resin-coated Al cans.
Linkages Between Air Pollution and the Health Burden From COVID-19: Methodological Challenges and Opportunities
Authors: Benmarhnia Tarik 
Published: July 2020

Abstract
The coronavirus disease 2019 (COVID-19) pandemic revealed and exacerbated existing social and economic health disparities, and actionable epidemiologic evidence is needed to identify potential vulnerability factors to help inform targeted responses. In this commentary, methodological challenges and opportunities regarding the links between air pollution and COVID-19 are discussed with a focus on 2 factors: 1) the role of differential exposure to air pollution across populations as an explanation for spatiotemporal variability of the epidemic spread and resultant mortality; and 2) the indirect impacts of interventions to control COVID-19 person-to-person spread treated as natural experiments on air pollution and population health. I first discuss the potential mechanisms between exposure to air pollution and COVID-19 and the opportunity to clearly formulate causal questions of interest through the target trial framework. Then, I discuss challenges regarding the use of quasiexperimental designs that capitalize on the differential timing of COVID-19 policies including the selection of control groups and potential violations of the common shock assumption. Finally, I discuss environmental justice implications of this many-headed beast of a crisis.
En Bloc Capsulectomy for Breast Implant Illness: A Social Media Phenomenon?
Authors: Keane Grace , Chi David , Ha Austin Y , Myckatyn Terence M 
Published: July 2020

Abstract

Background
En bloc capsulectomy has recently increased in prominence as a potential surgical therapy for patients with breast implant illness (BII). However, this procedure has chiefly been recommended for treating breast implant-associated anaplastic large cell lymphoma (BIA-ALCL).

Objectives
This study aimed to review the current literature and evaluate the public understanding of treatment options for BII via social media to characterize any potential communication disconnect between clinicians and patients.

Methods
An electronic literature review was performed to identify all available publications mentioning evidence-based support for en bloc capsulectomy as treatment for BII and BIA-ALCL. Twitter social media posts referencing BII or BIA-ALCL were analyzed from 2010 to 2019. Author identity and any mention of surgical treatment were assessed.

Results
A total of 115 publications on the subject of BII and 315 articles on BIA-ALCL were identified. En bloc resection was recommended only for patients with a diagnosis of BIA-ALCL. A total of 6419 tweets referencing BII and 6431 tweets referencing BIA-ALCL were identified. Tweets referencing BIA-ALCL were significantly more likely to be authored by physicians (25.9% vs 5.3%, P &lt; 0.001), and tweets referencing BII were significantly more likely to mention any surgical treatment (7.8% vs 1.9%, P &lt; 0.001) and en bloc capsulectomy (1.4% vs 0.3%, P &lt; 0.001).

Conclusions
This study demonstrates that a communication disconnect exists between the scientific literature and social media regarding treatment options for BII and BIA-ALCL. Physicians should be aware of these potential misconceptions to empathetically address patient concerns in a patient-centered manner.
Protein-sol pKa: prediction of electrostatic frustration, with application to coronaviruses
Authors: Hebditch Max , Warwicker Jim 
Published: July 2020

Abstract

Motivation
Evolution couples differences in ambient pH to biological function through protonatable groups, in particular, those that switch from buried to exposed and alter protonation state in doing so. We present a tool focusing on structure-based discovery and display of these groups.

Results
Since prediction of buried group pKas is computationally intensive, solvent accessibility of ionizable groups is displayed, from which the user can iteratively select pKa calculation centers. Results are color-coded, with emphasis on buried groups. Utility is demonstrated with benchmarking against known pH sensing sites in influenza virus hemagglutinin and in variants of murine hepatitis virus, a coronavirus. A pair of histidine residues, which are conserved in coronavirus spike proteins, are predicted to be electrostatically frustrated at acidic pH in both pre- and post-fusion conformations. We suggest that an intermediate expanded conformation at endosomal pH could relax the frustration, allowing histidine protonation and facilitating conformational conversion of coronavirus spike protein.

Availability and implementation
This tool is available at http://www.protein-sol.manchester.ac.uk/pka/.
7 T imaging reveals a gradient in spinal cord lesion distribution in multiple sclerosis
Authors: Ouellette Russell , Treaba Constantina A , Granberg Tobias , Herranz Elena , Barletta Valeria , Mehndiratta Ambica , De Leener Benjamin , Tauhid Shahamat , Yousuf Fawad , Dupont Sarah M , Klawiter Eric C , Sloane Jacob A , Bakshi Rohit , Cohen-Adad Julien , Mainero Caterina 
Published: July 2020

AbstractWe used 7 T MRI to: (i) characterize the grey and white matter pathology in the cervical spinal cord of patients with early relapsing-remitting and secondary progressive multiple sclerosis; (ii) assess the spinal cord lesion spatial distribution and the hypothesis of an outside-in pathological process possibly driven by CSF-mediated immune cytotoxic factors; and (iii) evaluate the association of spinal cord pathology with brain burden and its contribution to neurological disability. We prospectively recruited 20 relapsing-remitting, 15 secondary progressive multiple sclerosis participants and 11 age-matched healthy control subjects to undergo 7 T imaging of the cervical spinal cord and brain as well as conventional 3 T brain acquisition. Cervical spinal cord imaging at 7 T was used to segment grey and white matter, including lesions therein. Brain imaging at 7 T was used to segment cortical and white matter lesions and 3 T imaging for cortical thickness estimation. Cervical spinal cord lesions were mapped voxel-wise as a function of distance from the inner central canal CSF pool to the outer subpial surface. Similarly, brain white matter lesions were mapped voxel-wise as a function of distance from the ventricular system. Subjects with relapsing-remitting multiple sclerosis showed a greater predominance of spinal cord lesions nearer the outer subpial surface compared to secondary progressive cases. Inversely, secondary progressive participants presented with more centrally located lesions. Within the brain, there was a strong gradient of lesion formation nearest the ventricular system that was most evident in participants with secondary progressive multiple sclerosis. Lesion fractions within the spinal cord grey and white matter were related to the lesion fraction in cerebral white matter. Cortical thinning was the primary determinant of the Expanded Disability Status Scale, white matter lesion fractions in the spinal cord and brain of the 9-Hole Peg Test and cortical thickness and spinal cord grey matter cross-sectional area of the Timed 25-Foot Walk. Spinal cord lesions were localized nearest the subpial surfaces for those with relapsing-remitting and the central canal CSF surface in progressive disease, possibly implying CSF-mediated pathogenic mechanisms in lesion development that may differ between multiple sclerosis subtypes. These findings show that spinal cord lesions involve both grey and white matter from the early multiple sclerosis stages and occur mostly independent from brain pathology. Despite the prevalence of cervical spinal cord lesions and atrophy, brain pathology seems more strongly related to physical disability as measured by the Expanded Disability Status Scale.
The Hague Judgments Convention and How We Negotiated It
Authors: Sun Jin , Wu Qiong 
Published: July 2020

Abstract
In July 2019, the Hague Conference on Private International Law adopted the Convention on the Recognition and Enforcement of Foreign Judgments in Civil or Commercial Matters. As an outcome of the Judgments Project, this Convention will exert a great influence on the global circulation of foreign judgments. China attached great importance to the Judgments Project and participated in the full negotiation process. This paper is a reflection of some of the Chinese negotiators’ approaches in handling certain very difficult but important issues in the process, with the hope that it may shed some light on China’s negotiation practice and the principles it adheres to in the international law arena, which are fully in line with the principles of equity and justice, mutual benefit, and win-win outcome.
The Impact of Weather and Air Pollution on Viral Infection and Disease Outcome Among Pediatric Pneumonia Patients in Chongqing, China, from 2009 to 2018: A Prospective Observational Study
Authors: Wang Zhi-Bo , Ren Luo , Lu Qing-Bin , Zhang Xiao-Ai , Miao Dong , Hu Yuan-Yuan , Dai Ke , Li Hao , Luo Zheng-Xiu , Fang Li-Qun , Liu En-Mei , Liu Wei 
Published: July 2020

Abstract

Background
For pediatric pneumonia, the meteorological and air pollution indicators have been frequently investigated for their association with viral circulation but not for their impact on disease severity.

Methods
We performed a 10-year prospective, observational study in 1 hospital in Chongqing, China, to recruit children with pneumonia. Eight commonly seen respiratory viruses were tested. Autoregressive distributed lag (ADL) and random forest (RF) models were used to fit monthly detection rates of each virus at the population level and to predict the possibility of severe pneumonia at the individual level, respectively.

Results
Between 2009 and 2018, 6611 pediatric pneumonia patients were included, and 4846 (73.3%) tested positive for at least 1 respiratory virus. The patient median age was 9 months (interquartile range, 4‒20). ADL models demonstrated a decent fitting of detection rates of R2 &gt; 0.7 for respiratory syncytial virus, human rhinovirus, parainfluenza virus, and human metapneumovirus. Based on the RF models, the area under the curve for host-related factors alone was 0.88 (95% confidence interval [CI], .87‒.89) and 0.86 (95% CI, .85‒.88) for meteorological and air pollution indicators alone and 0.62 (95% CI, .60‒.63) for viral infections alone. The final model indicated that 9 weather and air pollution indicators were important determinants of severe pneumonia, with a relative contribution of 62.53%, which is significantly higher than respiratory viral infections (7.36%).

Conclusions
Meteorological and air pollution predictors contributed more to severe pneumonia in children than did respiratory viruses. These meteorological data could help predict times when children would be at increased risk for severe pneumonia and when interventions, such as reducing outdoor activities, may be warranted.
Capital as ‘abstraction in action’ and economic rhythms in Marx
Authors: Tombazos Stavros 
Published: July 2020

AbstractCapital, as self-valorising value, abstraction in action, Hegelian syllogism or self-organisation of economic rhythms oriented to the unique goal of profit production, is based on the reversal of subject and object in capitalist society. The producer is subjugated to their own social relationship that acts as a subject and treats them as its object. The fetishism of social reproduction manifests itself more clearly in structural crises, in which the system persists only through accelerated social regression.
Haemodialysis and peritoneal dialysis patients have severely impaired post-occlusive skin forearm vasodilatory response assessed with laser speckle contrast imaging
Authors: Alexandrou Maria-Eleni , Gkaliagkousi Εugenia , Loutradis Charalampos , Dimitriadis Chrysostomos , Mitsopoulos Efstathios , Lazaridis Antonios , Nikolaidou Barbara , Dolgiras Panagiotis , Douma Stella , Papagianni Aikaterini , Sarafidis Pantelis A 
Published: July 2020

Abstract

Background
Endothelial dysfunction is associated with cardiovascular events and mortality in various disease states, including end-stage renal disease (ESRD). Novel technological approaches have emerged for real-time assessment of endothelial reactivity. This study examined skin microcirculation using laser speckle contrast imaging (LSCI) before and after arterial occlusion in ESRD patients undergoing haemodialysis (HD) or peritoneal dialysis (PD).

Methods
The 38 HD patients were matched in a 1:1 ratio with 38 PD patients (for age, sex and dialysis vintage) and 38 controls (for age and sex). Skin microvascular reactivity parameters assessed with LSCI included baseline perfusion, occlusion perfusion and peak perfusion during post-occlusive reactive hyperaemia (PORH); time to peak perfusion; proportional change from baseline to peak perfusion; baseline and peak cutaneous vascular conductance (CVC); proportional change from baseline to peak CVC and amplitude of the PORH response (i.e. the difference between peak and baseline CVC).

Results
Baseline perfusion [HD: 46.97 ± 14.6; PD: 49.32 ± 18.07; controls: 42.02 ± 11.94 laser specle perfusion units (LSPU), P = 0.097] and peak post-occlusion perfusion (104.77 ± 28.68 versus 109.04 ± 40.77 versus 116.96 ± 30.96 LSPU, P = 0.238) did not differ significantly between groups. However, the post-occlusive vascular response was completely different since the proportional increase from baseline to peak perfusion (HD: 133 ± 66; PD: 149 ± 125; controls: 187 ± 61%, P = 0.001) was significantly lower in ESRD patients and time to peak response was lower in HD but similar in PD patients compared with controls (HD: 7.24 ± 6.99; PD: 10.68 ± 9.45; controls: 11.11 ± 5.1 s, Kruskal–Wallis P = 0.003; pairwise comparisons: HD versus controls, P = 0.002; HD versus PD, P = 0.154; PD versus controls, P = 0.406). ESRD patients also had lower levels of peak CVC, indicating the maximum capillary recruitment (HD: 1.05 ± 0.3; PD: 1.07 ± 0.44; controls: 1.57 ± 0.52 LSPU/mmHg, P &lt; 0.001), lower proportional increase of CVC at peak (P &lt; 0.001) and lower amplitude of the PORH response, a measure of the difference between baseline and maximum capillary recruitment (P = 0.001).

Conclusions
Using this novel non-invasive technology, endothelial post-occlusive forearm skin vasodilatory response was found to be similar between HD and PD patients and significantly impaired compared with controls. Future studies are needed to assess the prognostic implications of this microcirculatory functional defect.