bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficient and exact sampling of transition path ensembles on Markovian networks
Authors: Sharpe Daniel J. , Wales David J.
Published: July 2020

The problem of flickering trajectories in standard kinetic Monte Carlo (kMC) simulations prohibits sampling of the transition path ensembles (TPEs) on Markovian networks representing many slow dynamical processes of interest. In the present contribution, we overcome this problem using knowledge of the metastable macrostates, determined by an unsupervised community detection algorithm, to perform enhanced sampling kMC simulations. We implement two accelerated kMC methods to simulate the nonequilibrium stochastic dynamics on arbitrary Markovian networks, namely, weighted ensemble (WE) sampling and kinetic path sampling (kPS). WE-kMC utilizes resampling in pathway space to maintain an ensemble of representative trajectories covering the state space, and kPS utilizes graph transformation to simplify the description of an escape trajectory from a trapping energy basin. Both methods sample individual trajectories governed by the linear master equation with the correct statistical frequency. We demonstrate that they allow for efficient estimation of the time-dependent occupation probability distributions for the metastable macrostates, and of TPE statistics, such as committor functions and first passage time distributions. kPS is particularly attractive, since its efficiency is essentially independent of the degree of metastability, and we suggest how the algorithm could be coupled with other enhanced sampling methodologies. We illustrate our approach with results for a network representing the folding transition of a tryptophan zipper peptide, which exhibits a separation of characteristic timescales. We highlight some salient features of the dynamics, most notably, strong deviations from two-state behavior, and the existence of multiple competing mechanisms.
Machine-learning approach for constructing control landscape maps of three-dimensional alignment of asymmetric-top molecules
Authors: Namba Tomotaro , Yoshida Masataka , Ohtsuki Yukiyoshi
Published: July 2020

A machine-learning approach to draw landscape maps in a low-dimensional control-parameter space is examined through a case study of three-dimensional alignment control of the asymmetric-top molecule SO2. As a minimal model, we consider the control by using a set of mutually orthogonal, linearly polarized laser pulses that are parameterized by the time delay and fluence ratio. The parameters are represented either by points in the parameter space or by time- and frequency-resolved spectra. Machine-learning models based on convolutional neural networks together with two considerably different representations, which are trained by using a reasonably small number of training samples, construct maps that have sufficient accuracy to predict temperature-dependent control mechanisms.
Interstitial defects in diamond: A quantum mechanical simulation of their EPR constants and vibrational spectra
Authors: Colasuonno Fabio , Gentile Francesco Silvio , Mackrodt William , Ferrari Anna Maria , Platonenko Alexander , Dovesi Roberto
Published: July 2020

The local geometry, electronic structure, and vibrational features of three vicinal double interstitial defects in diamond, ICIC, ICIN, and ININ, are investigated and compared with those of three “simple” ⟨100⟩ interstitial defects, ICC, ICN, and INN, previously reported by Salustro et al. [Phys. Chem. Chem. Phys. 20, 16615 (2018)], using a similar quantum mechanical approach based on the B3LYP functional constructed from Gaussian-type basis sets, within a supercell scheme, as implemented in the CRYSTAL code. For the first time, the Fermi contact term and hyperfine coupling tensor B of the four open shell structures, ICIC, ICIN, ICC, and ICN, are evaluated and compared with the available experimental EPR data. For the two double interstitial defects, the agreement with experiment is good, whereas that for the single interstitials is found to be very poor, for which a likely reason is the incorrect attribution of the EPR spectra to uncertain atomic details of the micro-structure of the samples. The infrared spectra of the three double interstitial defects exhibit at least two peaks that can be used for their characterization.
Where words get their meaning
Authors: Bolognesi Marianna
Published: July 2020

Words are not just labels for conceptual categories. Words construct conceptual categories, frame situations and influence behavior. Where do they get their meaning?
This book describes how words acquire their meaning. The author argues that mechanisms based on associations, pattern detection, and feature matching processes explain how words acquire their meaning from experience and from language alike. Such mechanisms are summarized by the distributional hypothesis, a computational theory of meaning originally applied to word occurrences only, and hereby extended to extra-linguistic contexts.
By arguing in favor of the cognitive foundations of the distributional hypothesis, which suggests that words that appear in similar contexts have similar meaning, this book offers a theoretical account for word meaning construction and extension in first and second language that bridges empirical findings from cognitive and computer sciences. Plain language and illustrations accompany the text, making this book accessible to a multidisciplinary academic audience.
Mesenchymal stromal cell‐derived small extracellular vesicles restore lung architecture and improve exercise capacity in a model of neonatal hyperoxia‐induced lung injury
Authors: Willis Gareth R. , Fernandez‐Gonzalez Angeles , Reis Monica , Yeung Vincent , Liu Xianlan , Ericsson Maria , Andrews Nick A. , Mitsialis S. Alex , Kourembanas Stella
Published: July 2020

Early administration of mesenchymal stromal cell (MSC)‐derived small extracellular vesicles (MEx) has shown considerable promise in experimental models of bronchopulmonary dysplasia (BPD). However, the ability of MEx to reverse the long‐term pulmonary complications associated with established BPD remains unknown. In this study, MEx were isolated from media conditioned by human Wharton's Jelly‐derived MSC cultures. Newborn mice (FVB strain) were exposed to hyperoxia (HYRX (75% O2)) before returning to room air at postnatal day 14 (PN14). Following prolonged HYRX‐exposure, animals received a single MEx dose at PN18 or serial MEx treatments at PN18‐39 (“late” intervention). This group was compared to animals that received an early single MEx dose at PN4 (“early” intervention). Animals were harvested at PN28 or 60 for assessment of pulmonary parameters. We found that early and late MEx interventions effectively ameliorated core features of HYRX‐induced neonatal lung injury, improving alveolar simplification, pulmonary fibrosis, vascular remodelling and blood vessel loss. Exercise capacity testing and assessment of pulmonary hypertension (PH) showed functional improvements following both early and late MEx interventions. In conclusion, delivery of MEx following prolonged HYRX‐exposure improves core features of experimental BPD, restoring lung architecture, decreasing pulmonary fibrosis and vascular muscularization, ameliorating PH and improving exercise capacity. Taken together, delivery of MEx may not only be effective in the immediate neonatal period to prevent the development of BPD but may provide beneficial effects for the management and potentially the reversal of cardiorespiratory complications in infants and children with established BPD.
The kinesin-like protein Pavarotti functions noncanonically to regulate actin dynamics
Authors: Nakamura Mitsutoshi , Verboon Jeffrey M. , Prentiss Clara L. , Parkhurst Susan M.
Published: July 2020

Pavarotti, the Drosophila MKLP1 orthologue, is a kinesin-like protein that works with Tumbleweed (MgcRacGAP) as the centralspindlin complex. This complex is essential for cytokinesis, where it helps to organize the contractile actomyosin ring at the equator of dividing cells by activating the RhoGEF Pebble. Actomyosin rings also function as the driving force during cell wound repair. We previously showed that Tumbleweed and Pebble are required for the cell wound repair process. Here, we show that Pavarotti also functions during wound repair and confirm that while Pavarotti, Tumbleweed, and Pebble are all used during this cellular repair, each has a unique localization pattern and knockdown phenotype, demonstrating centralspindlin-independent functions. Surprisingly, we find that the classically microtubule-associated Pavarotti binds directly to actin in vitro and in vivo and has a noncanonical role directly regulating actin dynamics. Finally, we demonstrate that this actin regulation by Pavarotti is not specific to cellular wound repair but is also used in normal development.
Characterisation of Au surface properties relevant for UV photoemission-based charge control for space inertial sensors
Authors: Olatunde Taiwo , Apple Stephen , Inchauspé Henri , Parry Samantha , Letson Benjamin , Wass Peter J , Mueller Guido , Conklin John W
Published: July 2020

Precision space inertial sensors used for satellite geodesy missions, tests of fundamental physics, and gravitational wave observation utilise UV photoemission to control the electric potential of free-falling test masses with respect to their surrounding electrode housings. Successful generation of photoelectrons requires UV light energies greater than the work function of the illuminated surface. To ensure bi-polar test mass charge control (positive and negative charge rates), the quantum yields of the test mass and electrode housing surfaces must be well-balanced. LISA Pathfinder used mercury vapour lamps at 254 nm to discharge the gold coated test mass by likely relying on contaminants to lower the work function of gold from its nominal value of 5.2 eV. The LISA gravitational wave mission plans to use UV light emitting diodes (LEDs) instead of mercury vapour lamps. These UV LEDs have a lower mass, higher power efficiency, and produce light at wavelengths below 240 nm. In this paper, we measure the quantum yields of several Au-coated surfaces over a range of UV wavelengths and environmental conditions, varying temperature, vacuum pressure, and measuring over long periods of time. We use these data to draw conclusions and make recommendations for the development and handling of precision space inertial sensors for LISA and for other missions in the future.
Comprehensive model and performance optimization of phase-only spatial light modulators
Authors: A Pushkina A , I Costa-Filho J , Maltese G , I Lvovsky A
Published: July 2020

Several spurious effects are known to degrade the performance of phase-only spatial light modulators. We introduce a comprehensive model that takes into account the major ones: curvature of the back panel, pixel crosstalk and the internal Fabry–Perot cavity. To estimate the model parameters with high accuracy, we generate blazed grating patterns and acquire the intensity response curves of the first and second diffraction orders. The quantitative model is used to generate compensating holograms, which can produce optical modes with high fidelity.
Lightweight mechanical metamaterials designed using hierarchical truss elements
Authors: Mizzi Luke , Spaggiari Andrea
Published: July 2020

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

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

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

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

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

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

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

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 < 0.001), and tweets referencing BII were significantly more likely to mention any surgical treatment (7.8% vs 1.9%, P < 0.001) and en bloc capsulectomy (1.4% vs 0.3%, P < 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

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

We 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

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

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 > 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

Capital, 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

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 < 0.001), lower proportional increase of CVC at peak (P < 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.
Maximum likelihood estimation for randomized shortest paths with trajectory data
Authors: Kivimäki Ilkka , Van Moorter Bram , Panzacchi Manuela , Saramäki Jari , Saerens Marco
Published: July 2020

Randomized shortest paths (RSPs) are tool developed in recent years for different graph and network analysis applications, such as modelling movement or flow in networks. In essence, the RSP framework considers the temperature-dependent Gibbs–Boltzmann distribution over paths in the network. At low temperatures, the distribution focuses solely on the shortest or least-cost paths, while with increasing temperature, the distribution spreads over random walks on the network. Many relevant quantities can be computed conveniently from this distribution, and these often generalize traditional network measures in a sensible way. However, when modelling real phenomena with RSPs, one needs a principled way of estimating the parameters from data. In this work, we develop methods for computing the maximum likelihood estimate of the model parameters, with focus on the temperature parameter, when modelling phenomena based on movement, flow or spreading processes. We test the validity of the derived methods with trajectories generated on artificial networks as well as with real data on the movement of wild reindeer in a geographic landscape, used for estimating the degree of randomness in the movement of the animals. These examples demonstrate the attractiveness of the RSP framework as a generic model to be used in diverse applications.
Language and the National Past in Napoleonic France: Reassessing the Académie celtique, 1805–1813
Authors: Stewart Ian B
Published: July 2020

This article reassesses the Académie celtique (1805–13), an antiquarian society concerned with investigating the origins of the French nation, and the progenitor of the current Société nationale des antiquaires de France. While most prior scholarship has focused on the Académie as an innovator in the field of French folklore studies, it is argued here that the Académie’s main scholarly concern was with language, specifically the use of historical linguistic research for tracing the origins of European nations. Underpinning the Académie’s research programme was a belief that the ancient Celts—based in Gaul—once dominated Europe and spoke a language from which most European tongues descended, and was perhaps preserved in modern Breton. The article therefore also presents a coherent view of the importance of Celtic ancestry for the developing French nation in the early nineteenth century.
Upregulation of PD-L1 expression promotes epithelial-to-mesenchymal transition in sorafenib-resistant hepatocellular carcinoma cells
Authors: Xu Gui-Li , Ni Cai-Fang , Liang Han-Si , Xu Yun-Hua , Wang Wan-Sheng , Shen Jian , Li Ming-Ming , Zhu Xiao-Li
Published: July 2020

Background

The epithelial-to-mesenchymal transition (EMT) status is associated with programmed death-1 ligand 1 (PD-L1) expression in various cancers. However, the role and molecular mechanism of PD-L1 in the EMT of sorafenib-resistant hepatocellular carcinoma (HCC) cells remain elusive. In this study, we aimed to investigate the regulation of PD-L1 on the EMT in sorafenib-resistant HCC cells.

Methods

Initially, the sorafenib-resistant HCC cell lines HepG2 SR and Huh7 SR were established. Western-blot assays were used to detect the expression of PD-L1, E-cadherin, and N-cadherin. The intervention and overexpression of PD-L1 were used to explore the role of PD-L1 in the regulation of EMT in HepG2 SR and Huh7 SR cells. Cell migration and invasion were assessed by transwell assays. PD-L1 or Sterol regulatory element-binding protein 1 (SREBP-1) overexpression and knock-down were performed in order to study the mechanism of PD-L1 in sorafenib-resistant HCC cells.

Results

PD-L1 expression was upregulated, whereas E-cadherin levels were downregulated and N-cadherin expression was increased in HepG2 SR and Huh7 SR cells. The cell viabilities of HepG2 and Huh7 cells were lower than those of HepG2 SR and Huh7 SR cells. PD-L1 overexpression reduced E-cadherin expression and increased N-cadherin levels, whereas PD-L1 knock-down increased E-cadherin expression and decreased N-cadherin expression. PD-L1 expression promoted EMT and the migratory and invasive abilities of HepG2 SR and Huh7 SR cells. PD-L1 promoted the EMT of sorafenib-resistant HCC cells via the PI3K/Akt pathway by activating SREBP-1 expression in HepG2 SR and Huh7 SR cells.

Conclusions

The findings reveal that PD-L1 expression promotes EMT of sorafenib-resistant HCC cells.
Loneliness as a Biographical Disruption—Theoretical Implications for Understanding Changes in Loneliness
Authors: Morgan Deborah J , Burholt Vanessa
Published: July 2020

Objectives

While a great deal is known about the risk factors that increase vulnerability to loneliness in later life, little research has explored stability and change in levels of loneliness.

Methods

Narrative interviews were conducted with 11 participants who were identified as being lonely during Wave 1 of the Maintaining Function and Well-being in Later Life Study Wales (CFAS Wales). The interviews were used to explore stability and change in levels of loneliness from the perspective of older people themselves. The interviews focused on participant’s perspectives of the events that triggered loneliness, stability, and change in levels of loneliness over time as well as participant’s responses to loneliness.

Results

The findings show that participants experienced losses and loneliness as biographical disruption. How participants and their wider social network responded to these losses had implications for the individual’s trajectory through loneliness.

Discussion

Drawing on a biographical lens, the study reframed the events that triggered loneliness as disruptive events. This article discusses the utility of biographical disruption in understanding stability and change in loneliness. The findings suggest how drawing on valued identities may help lonely adults transition out of loneliness.
Assessment of fecal DNA extraction protocols for metagenomic studies
Authors: Yang Fangming , Sun Jihua , Luo Huainian , Ren Huahui , Zhou Hongcheng , Lin Yuxiang , Han Mo , Chen Bing , Liao Hailong , Brix Susanne , Li Junhua , Yang Huanming , Kristiansen Karsten , Zhong Huanzi
Published: July 2020

Background

Shotgun metagenomic sequencing has improved our understanding of the human gut microbiota. Various DNA extraction methods have been compared to find protocols that robustly and most accurately reflect the original microbial community structures. However, these recommendations can be further refined by considering the time and cost demands in dealing with samples from very large human cohorts. Additionally, fungal DNA extraction performance has so far been little investigated.

Results

We compared 6 DNA extraction protocols, MagPure Fast Stool DNA KF Kit B, Macherey Nagel™ NucleoSpin™®Soil kit, Zymo Research Quick-DNA™ Fecal/Soil Microbe kit, MOBIO DNeasy PowerSoil kit, the manual non-commercial protocol MetaHIT, and the recently published protocol Q using 1 microbial mock community (MMC) (containing 8 bacterial and 2 fungal strains) and fecal samples. All samples were manually extracted and subjected to shotgun metagenomics sequencing. Extracting DNA revealed high reproducibility within all 6 protocols, but microbial extraction efficiencies varied. The MMC results demonstrated that bead size was a determining factor for fungal and bacterial DNA yields. In human fecal samples, the MagPure bacterial extraction performed as well as the standardized protocol Q but was faster and more cost-effective. Extraction using the PowerSoil protocol resulted in a significantly higher ratio of gram-negative to gram-positive bacteria than other protocols, which might contribute to reported gut microbial differences between healthy adults.

Conclusions

We emphasize the importance of bead size selection for bacterial and fungal DNA extraction. More importantly, the performance of the novel protocol MP matched that of the recommended standardized protocol Q but consumed less time, was more cost-effective, and is recommended for further large-scale human gut metagenomic studies.
How does firm innovation size affect the timing of technology licensing? Theory and evidence from China
Authors: Ma Rongkang , Zhu Shanshan , Liu Fengchao
Published: July 2020

Previous research has highlighted the importance of firm size for the propensity of technology licensing. However, the currently available knowledge regarding how firm innovation size affects the timing of technology licensing is limited, especially in developing economies such as that of China. Therefore, in the context of the Chinese patent system, this article builds a model for the timing decision of technology licensing from the perspective of licensors. This model theoretically reveals the relationship between firm innovation size and the likelihood of technology licensing at different time points. This article argues that there is a positive relationship between firm innovation size and the likelihood of technology licensing before the patent disclosure date; moreover, there is an inverted U-shaped relationship between the firm innovation size and the likelihood of licensing between the patent disclosure date and the grant date; however, firm innovation size is negatively correlated with the likelihood of licensing after the patent grant date. Empirical results based on 8737 first-time licensing data on invention patents of Chinese firms in 2001–2015 support all predictions. This study contributes to both the scholarly understanding of timing decision making in firms’ technology licensing and the design of technology transfer policies for different firms in China.
Near Real-Time Identification of Recent Human Immunodeficiency Virus Transmissions, Transmitted Drug Resistance Mutations, and Transmission Networks by Multiplexed Primer ID–Next-Generation Sequencing in North Carolina
Authors: Zhou Shuntai , Sizemore Sabrina , Moeser Matt , Zimmerman Scott , Samoff Erika , Mobley Victoria , Frost Simon , Cressman Andy , Clark Michael , Skelly Tara , Kelkar Hemant , Veluvolu Umadevi , Jones Corbin , Eron Joseph , Cohen Myron , Nelson Julie A E , Swanstrom Ronald , Dennis Ann M
Published: July 2020

Background

The identification of recent human immunodeficiency virus (HIV) 1 infections among people with new HIV diagnoses is important to both tailoring and assessing the impact of HIV-1 prevention strategies.

Methods

We developed a multiplexed Primer ID–next-generation sequencing approach to identify recent infections by measuring the intrahost viral diversity over multiple regions of the HIV-1 genome, in addition to detecting drug resistance mutations (DRMs) and phylogenetically linked clusters. We summarize the field implementation of this all-in-one platform among persons with newly diagnosed HIV-1 by the North Carolina State Laboratory of Public Health in 2018.

Results

Overall, recent infection was identified in 94 (35%) of 268 patients with new HIV diagnoses. People <30 years old, and people who inject drugs were more likely to have diagnoses of recent infection. The reverse-transcriptase region K103N was the most commonly detected DRM (prevalence, approximately 15%). We found a total of 28 clusters, and persons with recent infection were more likely to be cluster members than were those with chronic infections (P = .03).

Conclusions

We demonstrate the rapid identification of recent infection and pretreatment DRMs coupled with cluster analysis that will allow prioritization of linkage to care, treatment, and prevention interventions to those at highest risk of onward transmission.