bluuebunny/crossref_metadata_2025 huggingface dataset:
Astrophysical information from the Rayleigh-Jeans Tail of the CMB
Authors: Ghara Raghunath , Mellema Garrelt , Zaroubi Saleem
Published: March 2022

One of the explanations for the recent EDGES-LOW band 21 cm measurements of a strong absorption signal around 80 MHz is the presence of an excess radio background to the Cosmic Microwave Background (CMB). Such excess can be produced by the decay of unstable particles into small mass dark photons which have a non-zero mixing angle with electromagnetism. We use the EDGES-LOW band measurements to derive joint constraints on the properties of the early galaxies and the parameters of such a particle physics model for the excess radio background. A Bayesian analysis shows that a high star formation efficiency and X-ray emission of 4–7 × 1048 erg per solar mass in stars are required along with a suppression of star formation in halos with virial temperatures ≲ 2 × 104 K. The same analysis also suggests a 68 percent credible intervals for the mass of the decaying dark matter particles, it's lifetime, dark photon mass and the mixing angle of the dark and ordinary photon oscillation of [10-3.5, 10-2.4] eV, [101.1, 102.7] × 13.8 Gyr, [10-12.2, 10-10] eV and [10-7, 10-5.6] respectively. This implies an excess radio background which is ≈ 5.7 times stronger than the CMB around 80 MHz. This value is a factor ∼ 3 higher than the previous predictions which used a simplified model for the 21 cm signal.
A prediction for anisotropies in the nearby Hubble flow
Authors: Heinesen Asta , Macpherson Hayley J.
Published: March 2022

We assess the dominant low-redshift anisotropic signatures in the distance-redshift relation and redshift drift signals. We adopt general-relativistic irrotational dust models allowing for gravitational radiation — the `quiet universe models' — which are extensions of the silent universe models. Using cosmological simulations evolved with numerical relativity, we confirm that the quiet universe model is a good description on scales larger than those of collapsing structures.
With this result, we reduce the number of degrees of freedom in the fully general luminosity distance and redshift drift cosmographies by a factor of ∼ 2 and ∼ 2.5, respectively, for the most simplified case.
We predict a dominant dipolar signature in the distance-redshift relation for low-redshift data, with direction along the gradient of the large-scale density field. Further, we predict a dominant quadrupole in the anisotropy of the redshift drift signal, which is sourced by the electric Weyl curvature tensor. The signals we predict in this work should be tested with present and near-future cosmological surveys.
Charge-injection Device Imaging of Sirius with Contrast Ratios Greater than 1:26 Million
Authors: Sawant Sailee M. , Batcheldor Daniel
Published: March 2022

The intrinsic nature of many astronomical objects, such as binary and multiple systems, exoplanets, circumstellar and debris disks, and quasar host galaxies, introduces challenging requirements for observational instrumentation and techniques. In each case, we encounter situations where the light from bright sources hampers our ability to detect surrounding fainter targets. To explore all features of such astronomical scenes, we must perform observations at the maximum possible contrast ratios. Charge-injection devices (CIDs) are capable of potentially exceeding contrast ratios of

log

10

(
CR
)
>
9

(i.e., 1 part in 1 billion) due to their unique readout architectures and inherent anti-blooming abilities. An on-sky testing of a commercially available CID, SpectraCAM XDR (SXDR), demonstrated raw contrast ratios from sub-optimal ground-based astronomical observations that imposed practical limits on the maximum achievable contrast ratios using CIDs. Here, we demonstrate the extreme contrast ratio imaging capabilities of the SXDR using observations of Sirius with the 1.0 m Jacobus Kapteyn Telescope, La Palma, Spain. Based on wavelet-based analysis and precise photometric and astrometric calibrations, we report a direct contrast ratio of Δm

r
= 18.54,

log

10

(
CR
)
=
7.41
±
0.08

, or 1 part in 26 million. This is an order of magnitude higher compared to the previous CID results.
Characterization of pedestal burst instabilities during I-mode to H-mode transition in the EAST tokamak
Authors: Zhong X.M. , Zou X.L. , Liu A.D. , Song Y.T. , Zhuang G. , Li E.Z. , Zhang B. , Zhang J. , Zhou C. , Feng X. , Duan Y.M. , Ding R. , Liu H.Q. , Lv B. , Wang L. , Xu L.Q. , Zhang L. , Zhao H.L. , Zang Q. , Zhang T. , Ding B.J. , Li M.H. , Qin C.M. , Wang X.J. , Zhang X.J. , EAST Team
Published: March 2022

Quasi-periodic pedestal burst instabilities (PBIs), featuring alternative turbulence suppression and bursts, have been clearly identified by various edge diagnostics during I-mode to H-mode transition in the EAST Tokamak. The radial distribution of the phase perturbation caused by PBI shows that PBI is localized in the pedestal. Prior to each PBI, a significant increase of density gradient close to the pedestal top can be clearly distinguished, then the turbulence burst is generated, accompanied by the relaxation of the density profile, and then induces an outward particle flux. The relative density perturbation caused by PBIs is about 6%–8%. Statistic analyses show that the pedestal normalized density gradient R/L
n triggering the first PBI has a threshold value, mostly in the range of 22–24, suggesting that a PBI triggering instability could be driven by the density gradient. And R/L
n triggering the last PBI is about 30–40 and seems to increase with the loss power and the chord-averaged density. In addition, the frequency of PBI is likely to be inversely proportional to the chord-averaged density and the loss power. These results suggest that PBIs and the density gradient prompt increase prior to PBIs can be considered as the precursor for controlling I–H transition.
Global Nonsingular Fast Terminal Sliding Mode Control of Aerodynamic Heat Simulation Heating System Based on Linear Extended State Observer
Authors: Lv X D , Zhang G M , Ouyang H M , Pan H H , Bai Z Q
Published: March 2022

In this paper, a novel global nonsingular fast terminal sliding mode control (GNFTSMC) method based on linear extended state observer (LESO) is proposed for Aerodynamic Heat Simulation Heating System (AHSHS). The global nonsingular fast terminal sliding mode surface (GNFTSMS), comprising constant reaching law and LESO, establishes a closed-loop control for the whole control process. Firstly, the designed GNFTSMS eliminates the reaching stage, so that the whole control process is confined on the sliding mode surface. The fast term and nonsingular term ensure convergence speed in the sliding phase, and eliminate the singularity and suppress the chattering phenomenon. Then, the constant reaching law can effectively solve the problem of convergence stagnation in the control process and further accelerate the convergence speed. Then, LESO can feed back the observation of input disturbances and external disturbances to the control system. Furthermore, Lyapunov stability theorem is utilized to prove the stability of the closed-loop system. Finally, the simulation results verify that the proposed GNFTSMC method based on LESO is superior.
PID Control of Permanent Magnet Synchronous Motor Based on Improved Actor-Critic Framework
Authors: Liao Junrong , Liu Shiyue , Wu Qinghe , Chen Jiabin , Wei Fuhua
Published: March 2022

Aiming at the shortcomings of the traditional PID control method that the parameters cannot be adjusted flexible, an improved Actor-Critic reinforcement learning algorithm combined with incremental PID control is proposed to improve the control performance of permanent magnet synchronous motor (PMSM). The strategy function of Actor and value function of Critic are approximated by two back propagation (BP) neural networks respectively. The simulation results show that the proposed algorithm has better control performance and effect than the traditional PID control method.
A Robust Backstepping Sliding Mode Controller with Chattering-Free Strategy for a Swarm of Drones
Authors: Zaidi Adeel , Kazim Muhammad , Wang Hui
Published: March 2022

This paper presents a robust controller for a swarm of drones that are subjected to external disturbances. Integrating a fuzzy-based system in the sliding mode control technique, a chattering-free controller is proposed for the trajectory tracking of a drone. Furthermore, the formation controller for a group of drones is developed using the Backstepping control design technique. The integration of a fuzzy rule-based system in the sliding mode tracking controller enables overcoming the inherent chattering problem due to discontinuous switching function in the sliding mode control technique and provides smooth and chattering-free control signals. The asymptotic stability of the overall system is shown using the Lyapunov stability theory. Finally, the control design performance is evaluated using numerical simulations.
Study on the Preparation and Properties of Several Dielectric Composites Applied to Capacitors
Authors: Mao Xin , Jiang Qin , Xu Luopeng , Liang Zhenyu , Shi Chenhui , Liu Xiang
Published: March 2022

Polyaniline, polyvinylidene fluoride or liquid acrylonitrile-butadiene rubber as high-dielectric organic fillers were added to the polyimide matrix to synthesize several all-organic polyimide-based dielectric composite materials, and then dielectric properties and energy storage density of these composites were investigated. Experimental results indicated that the dielectric properties of the three polyimide matrix composites were enhanced through the introduction of fillers. In addition, compared with Polyaniline or polyvinylidene fluoride as fillers, the composites prepared by liquid acrylonitrile-butadiene rubber as fillers exhibited superior dielectric properties and energy storage density.
Ensemble Learning based Fishing Behavior Analysis for Vessels around Zhoushan Islands Erea
Authors: Zhang Liang , Xing Bowen , Chen Xiao , Wang Wugui
Published: March 2022

In order to improve and verify the application value of AIS data in fishing behavior analysis, three existing models were chosen to analyze the fishing paths of more than 200 boats around Zhoushan Islands. In order to confirm their operation mode, F1-score was used to evaluate related models. Experimental results shown that the Lightgbm model embodies better performance in the analysis of fishing boat behavior with higher practicality.
Video-Assisted Clinical Care for Remote Management of COVID-19
Authors: Suhr Katelyn Alexa , Norouzi Narges , Julie Ian Michael
Published: March 2022

Due to the COVID-19 pandemic, the need for biomedical monitoring devices has increased for collecting vital signs from patients virtually. This paper will discuss developing an iOS mobile application that will ingest video frames in real-time to provide oxygen saturation and heart rate values. We provide two techniques for capturing data using 1) face monitoring under natural light and 2) fingertip monitoring using the iPhone’s flashlight. We observed an average Root Mean Squared Error (RMSE) of 3.6 for heart rate estimation using fingertip recordings and 13.25 using face recordings. For oxygen saturation, we obtained the RMSE for each class between SpO2 values 94 - 99%. The lowest RMSE provided from our application was 0.26 for fingertip recording and 0.22 for face recording at SpO2 level 96%. The highest RMSE was 6.34 for fingertip recording and 6.56 for face recording at SpO2 level 99%. These preliminary models will be further enhanced through a clinical study with UC Davis Health as we collect data from participants with respiratory diseases.
Design and Mechanics Analysis of Tools for Live Replacement of UHV Whole String Insulators
Authors: Xuechun HAN , Hengdong SONG , Xmglie LEI , Yong PENG
Published: March 2022

The experimental results show that the method can effectively detect the contamination degree of the contact net insulator The replacement of whole string insulators is difficult tasks of live working for UHV transmission line and still remain blank. Based on the structure and layout of straight string and tensile string insulators of UHV transmission lines, this paper proposes design of tools for live replacement of the whole string insulators. Through three-dimensional simulation and analysis, the force characteristics of the various tools are determined, and developed the tools for live replacement of the whole string insulators of UHV, and the mechanical test of the tools are carried out. The test results confirm the feasibility of the tool design and the reliability of the mechanical simulation model proposed in this paper, which provides technical supports for the live replacement of UHV whole string insulators.
Ester-based Dielectric Fluid for Power Transformers: Design and Test Experience under the GreenEst Project
Authors: Carvalhosa Salvador , Leite Helder , Soares Mário , Branco Fábio , Sá Carlos A. , Lopes Ricardo Castro , Santo Joáo Espírito
Published: March 2022

Ester-based dielectric fluids have now been on the market for several decades, providing fire-safe and environmentally friendly alternatives to mineral oils, which have traditionally been used in transformers and other electrical equipment. This opens the door to innovation in power transformers. However, the use of esters-based dielectrics in power transformers is still very limited, especially for the higher voltage levels. The usage of these esters-based dielectrics in higher voltage power transformers is not yet consensual. this work present results with the use of natural esters in power distribution transformers. Tests carried out on mineral oil and natural ester oil found that the ester-based dielectric can withstand higher voltage thresholds for AC and Impulses tests, mainly within the specs of destructive tests, e.g., the natural ester was able to withstand a 185kV impulse without registering dielectric rupture while the natural oil registered a dielectric rupture with a 160kV impulse. Heating and mechanical tests demonstrated that ester-based dielectric oils for power transformers lead to a flow reduction between 16,8% and 18,2% in the cooling system that was design for mineral oils but they achieve a higher heat transfer coefficient, between 0,5% to 5% depending on the location of measurement.
Design Optimization Method and Performance Analysis of 90MW Grid-Connected Solar PV system in Cambodia
Authors: Sok Mean , Tao Hai
Published: March 2022

Large-scale PV plants have the ability to make the curtailment of cost per watt of the normal power installed. This article describes a new technique for computing the optimal contour of large PV plants. Massive infiltration of renewable energy sources is increasing because of the awareness created on environmental issues and electric power deregulation. A PV system is a renewable energy source that establishes a future sustainability in power distribution. The technical specifications details are provided by solar irradiation and performance ratio. High accuracy of energy generation followed in computations in the proposed system. The high-accuracy feature is validated using experimental data of the 90MW PV plant in Cambodia. The results obtained show that the optimisation method can lead to a reduced cost of energy generated. This enables the maximisation of the benefit obtained on the operational life period of the PV module. The model’s accuracy depends on a hierarchical structure level model, model measurement accuracy, model identification, structure accuracy, measurement accuracy, simulator algorithms metrics, and the accuracy of the calibration parameter. The paper is built based on the physical ranking of the PV power model structure, making the system a high-fidelity model.
Research on Motion Path Planning Method of Live Working Robot Manipulator Based on Reverse Splitting Calculation
Authors: Liu Zhe , Pan Aiqiang , Jiang Anfeng , Li Wenhe , Zhang Jiawei , Bai Chengchao
Published: March 2022

In the dual manipulator motion planning of live working robot, the traditional motion planning algorithm has the problems of too many turning points and non-smoothness. Therefore, this paper proposes a method of reverse splitting and local interpolation to remove redundant path nodes and optimize the motion trajectory. The working scene of overhead distribution line live working robot is simulated in MATLAB robot toolbox. The model includes manipulator R, manipulator L and overhead conductor to verify the effect of the method proposed in this paper. The results show that, the proposed method ensures that the redundant path nodes are removed on the premise of no collision between the two manipulators, which significantly improves the quality of the path.
Mechanical design of a passive lower-limb exoskeleton for load-carrying assistance
Authors: Liu J H , Li B , Ning Q , Zhou M , Li Y X , Liu M C , Xu K
Published: March 2022

This paper presents a passive exoskeleton with 17 degrees-of-freedom (DOF) for load-carrying, which includes two 3DOFs ankle joint, two 2DOFs hip joint, two 1DOF knee joint, one 1DOF backpack, and two redundant DOFs at the thigh and shank, respectively, to improve the compatibility of human-machine locomotion. The modular backpack was designed to facilitate carrying of different loads. A horn-shaped spatial mechanism was designed to connect the hip joint and the backpack, and transfer the payload to the ground. A tension spring was adopted to absorb the gravitational potential energy of the load when walking, and fix the horn-shaped spatial mechanism at both sides. The segmented brace at the thigh and the shank were designed to adjust different legs. In order to improve the force transmission performance, we cancelled the extension DOF of the hip joint, and moved the rotation axis of the knee joint backward. The knee joint assistance mechanism was designed to allow the knee joint move freely when the flexion angle did not exceed 60°. However, when the knee bends over 60°, the knee joint presses the torsion spring to store energy. After then, it releases energy to assist knee extending. The Cooper-Harper scale tests demonstrated that the exoskeleton had excellent static support effect and movement flexibility, which verified the rationality of the exoskeleton design.
A proposed high voltage distribution system for Mu2e electron tracker
Authors: Ahmed W. , Hungerford Ed. , MukeherJee A. , Russu V. , Tschirhart R. , Yucel M.
Published: March 2022

This paper reports on the design and construction of a High Voltage Distribution System (HVDS) for a “Smart Switch” developed to provide high voltage (HV) to a series of stacked straw detector planes in the Mu2e Electron Tracking Detector (ETD). Each plane is composed of three 120 deg. Crescent-shaped panels, and each panel is composed of 96 straw tubes. The HVDS provides HV on-off, current monitoring, recording, and crowbar for over-current protection. The inter-communication system is based on TCP/IP. The HVDS supplies HV with long term stability, and accurately monitors the applied voltage and currents.
Spatial patterns and drivers for wildfire ignitions in California
Authors: Chen Bin , Jin Yufang
Published: March 2022

As a key component of wildfire activities, ignition is regulated by complex interactions among climate, fuel, topography, and humans. Considerable studies have advanced our knowledge on patterns and drivers of total areas burned and fire frequency, but much is less known about wildfire ignition. To better design effective fire prevention and management strategies, it is critical to understand contemporary ignition patterns and predict the probability of wildfire ignitions from different sources. We here modeled and analyzed human- and lightning-caused ignition probability across the whole state and sub-ecoregions of California, USA. We developed maximum entropy models to estimate wildfire ignition probability and understand the complex impacts of anthropogenic and biophysical drivers, based on a historical ignition database. The models captured well the spatial patterns of human and lightning started wildfire ignitions in California. The human-caused ignitions dominated the areas closer to populated regions and along the traffic corridors. Model diagnosis showed that precipitation, slope, human settlement, and road network shaped the statewide spatial distribution of human-started ignitions. In contrast, the lightning-caused ignitions were distributed more remotely in Sierra Nevada and North Interior, with snow water equivalent, lightning strike density, and fuel amount as primary drivers. Separate region-specific model results further revealed the difference in the relative importance of the key drivers among different sub-ecoregions. Model predictions suggested spatially heterogeneous decadal changes and an overall slight decrease in ignition probability between circa 2000 and 2010. Our findings reinforced the importance of varying humans vs biophysical controls in different fire regimes, highlighting the need for locally optimized land management to reduce ignition probability.
All-optical investigations of intense femtosecond pulse ionization in transparent dielectrics with applications
Authors: Sahoo Anubhab , Rajeev P P , Krishnan Sivarama
Published: March 2022

Large bandgap optical media are transparent to near-infrared (NIR) and optical light pulses in the linear regime. However, at sufficiently high intensities, in their interaction with femtosecond (fs) laser pulses, nonlinear absorption takes place by multi-photon processes as well as field-assisted processes such as tunnel- and collisional-ionization. Their transparency to NIR and optical fs pulses enables in situ studies of nonlinear photoionization inside these media by all-optical transmission measurements. These measurements in tandem with suitable phenomenological models have paved the way towards a deeper understanding of dynamical processes. The ensuing dynamics can be categorized into two timescales: the first is a long pulse regime, for temporal duration τ

p
,

τ

p

>
100
 

f
s

, where laser driven electrons in these media gain sufficient kinetic energies by mechanisms such as inverse bremsstrahlung leading to electron avalanches. In the short pulse regime,

τ

p

<
100
 

f
s

, these electrons are excited to the conduction band by multiphoton absorption. In this article we present a perspective of the current status of research as well as results from our investigations. Not only do these studies provide facile means to study intriguing nonlinear photoionization processes, but they also probe these systems in a regime of intensities and pulse widths where micro- and nano-structuring as well as processing of materials by fs pulses are often realized. Further, these methods compliment research on coherent processes such as the generation of high-order harmonics and attosecond pulses in condensed phase media.
Risk of Chronic Kidney Disease Associated With Orthostatic Hypotensive Stress: A Community-Based Korean Study
Authors: Ko Hyun-Lee , Min Hyang-Ki , Lee Sung-Woo
Published: March 2022

Background

The relationship between orthostatic blood pressure (BP) changes and incident chronic kidney disease (CKD) has not been explored in Asian populations.

Methods

We reviewed the data of 7,039 participants from the Ansung-Ansan cohort study. BP was measured in the supine position and 2 minutes after standing. The change in BP from the supine to upright position was defined as orthostatic BP change. Orthostatic systolic BP (SBP) decline was defined as an orthostatic SBP change of <−2 mm Hg. The primary outcome was the development of CKD, defined as the first event of an estimated glomerular filtration rate <60 ml/min/1.73 m2 at least twice during the follow-up period.

Results

Of 7,039 participants, 949 (13.5 %) developed incident CKD over a mean of 11.9 years. Although orthostatic diastolic BP change was not associated with incident CKD, every 1 mm Hg increase in orthostatic SBP change was associated with a decreased risk of incident CKD (HR, 0.989; 95% CI, 0.982–0.995; P = 0.001). Orthostatic SBP decline was associated with an increased risk of incident CKD (HR, 1.337; 95% CI, 1.163–1.537; P < 0.001). Older age and diabetes were associated with increased odds of orthostatic SBP decline, whereas male sex and high body mass index were associated with decreased odds of orthostatic SBP decline. Subgroup analysis revealed that orthostatic SBP decline was associated with incident CKD only in non-diabetic participants.

Conclusions

Orthostatic SBP decline was independently associated with an increased risk of future incident CKD, whereas orthostatic DBP decline was not.
Daphnetin inhibits α-MSH-induced melanogenesis via PKA and ERK signaling pathways in B16F10 melanoma cells
Authors: Nam Garam , An Sung Kwan , Park In-Chul , Bae Seunghee , Lee Jae Ho
Published: March 2022

Daphnetin is a dehydroxylated derivative of coumarin isolated from Daphne species. However, the effect of daphnetin on melanogenesis has not been elucidated. This study aims to investigate the inhibitory effect of daphnetin on melanogenesis in α-melanocyte stimulating hormone (α-MSH)-treated B16F10 cells and its potential mechanism. Melanin content analysis and cellular tyrosinase activity assay showed that daphnetin inhibited melanin biosynthesis in α-MSH-treated B16F10 cells. Immunoblotting and qRT-PCR also indicated that daphnetin suppressed the expression of microphthalmia-associated transcription factor, a mastering transcription factor of melanogenesis and its downstream melanogenic enzymes including tyrosinase and tyrosinase-related proteins. Moreover, daphnetin downregulated the phosphorylation of PKA, ERK, MSK1, and CREB. Additionally, daphnetin inhibited melanin synthesis in UVB-irradiated HaCaT conditioned medium system suggesting that daphnetin has potential as an antipigmentation activity in a physiological skin condition. Our data propose that daphnetin inhibits melanogenesis via modulating both the PKA/CREB and the ERK/MSK1/CREB pathways.
Human lesions and animal studies link the claustrum to perception, salience, sleep and pain
Authors: Atilgan Huriye , Doody Max , Oliver David K. , McGrath Thomas M. , Shelton Andrew M. , Echeverria-Altuna Irene , Tracey Irene , Vyazovskiy Vladyslav V. , Manohar Sanjay G. , Packer Adam M.
Published: March 2022

The claustrum is the most densely interconnected region in the human brain. Despite the accumulating data from clinical and experimental studies, the functional role of the claustrum remains unknown. Here, we systematically review claustrum lesion studies and discuss their functional implications. Claustral lesions are associated with an array of signs and symptoms, including changes in cognitive, perceptual and motor abilities; electrical activity; mental state; and sleep. The wide range of symptoms observed following claustral lesions do not provide compelling evidence to support prominent current theories of claustrum function such as multisensory integration or salience computation. Conversely, the lesions studies support the hypothesis that the claustrum regulates cortical excitability. We argue that the claustrum is connected to, or part of, multiple brain networks that perform both fundamental and higher cognitive functions. As a multifunctional node in numerous networks, this may explain the manifold effects of claustrum damage on brain and behaviour.
Capital, Technology, and Time
Authors: Harris Donald J
Published: March 2022

This paper examines the substantive meaning and limitations of the concept of choice of technique, developed in the context of a test of logical consistency of the neoclassical parable concerning the relation between techniques of production and distribution of income in capitalist economies, and commonly used as a vehicle to support propositions about changes in technology. This concept is shown to rest on a foundation of logical time that is antithetical to a conception of historical time relevant to observed features of technological change. In this regard, it exposes a fundamental lacuna in the traditional neoclassical narrative and supporting theory related to the dual problems of agency and dynamics of the transition process involved in analysis of capital accumulation and technological change. There is room here for emerging alternative narratives to provide effective resolution of these problems.
Vergil ‘disrobed’: John Vicars’ ‘home-spun English gray-coat plain’ Aeneid (1632)
Authors: Braund Susanna
Published: March 2022

This article puts the spotlight upon the neglected 1632 translation of the entire Aeneid by the poet, puritan, and parliamentarian John Vicars, which, as the first complete translation of the Aeneid by an Englishman, should be more prominent in literary history. The article’s central argument is that the neglect of Vicars’ translation was, both at the time and thereafter, a manifestation of the class warfare that has long pervaded English society. This argument complements the view expressed by other scholars that the dismissal of Vicars was grounded in his radical puritanism and anti-Catholicism. The article analyses the paratextual materials that introduce the translation, including the dedicatory epistle, the address to the reader, and the poems of endorsement, as well as the poem itself, for signs of class struggle. By offering a close textual analysis, it argues that it is far from obvious that the quality of Vicars’ version is inferior. It concludes that the patent early hostility towards Vicars is more closely related to the person of the translator than the qualities of the translation; specifically, it attributes the failure of Vicars’ translation to dislike for the translator’s extremely humble origins, alongside his unfashionable religious and political views.
The puzzle of Valerii Briusov’s Aeneid
Authors: Martirosova Torlone Zara
Published: March 2022

The translation of the Aeneid by a leading Symbolist poet Valerii Briusov, on which he worked most of his life, failed to gain favor with Russian readers because of its literalism. Combining various theoretical approaches with a close analysis of the text this essay explores why Briusov’s translation failed in the context of the cultural and aesthetic demands of the era in which it was composed.
Extra food provisioning does not affect behavioral lateralization in nestling lesser kestrels
Authors: Soravia Camilla , Bisazza Angelo , Cecere Jacopo G , Rubolini Diego
Published: March 2022

Costs and benefits of brain lateralization may depend on environmental conditions. Growing evidence indicates that the development of brain functional asymmetries is adaptively shaped by the environmental conditions experienced during early life. Food availability early in life could act as a proxy of the environmental conditions encountered during adulthood, but its potential modulatory effect on lateralization has received little attention. We increased food supply from egg laying to early nestling rearing in a wild population of lesser kestrels Falco naumanni, a sexually dimorphic raptor, and quantified the lateralization of preening behavior (head turning direction). As more lateralized individuals may perform better in highly competitive contexts, we expected that extra food provisioning, by reducing the level of intra-brood competition for food, would reduce the strength of lateralization. We found that extra food provisioning improved nestling growth, but it did not significantly affect the strength or direction of nestling lateralization. In addition, maternal body condition did not explain variation in nestling lateralization. Independently of extra food provisioning, the direction of lateralization differed between the sexes, with female nestlings turning more often toward their right. Our findings indicate that early food availability does not modulate behavioral lateralization in a motor task, suggesting limited phenotypic plasticity in this trait.
The role of cardiac computed tomography in sports cardiology: back to the future!
Authors: D’Ascenzi Flavio , Baggiano Andrea , Cavigli Luna , Mandoli Giulia Elena , Andreini Daniele , Marallo Carmine , Valente Serafina , Focardi Marta , Cameli Matteo , Pontone Gianluca
Published: March 2022

In recent years, the role of pre-participation evaluation (PPE) in the prevention of sudden cardiac death in competitive athletes has become evident. Most physicians routinely supplement assessment by resting electrocardiogram with imaging techniques, such as echocardiography. The primary goal of imaging in the clinical assessment of competitive athletes is to exclude cardiovascular conditions associated with adverse outcomes. Cardiac computed tomography is emerging as an important technique for stratifying cardiovascular risk and assessing coronary artery disease (CAD), particularly in master athletes. Conversely, in young athletes, this technique has the best non-invasive coronary artery resolution and provides valuable details on coronary artery anatomy. Recent technical developments have brought about a dramatic reduction in radiation exposure, a major drawback of this diagnostic method; nowadays cardiac computed tomography may be performed at a dose of barely one millisievert. The present review provides a practical guide for the use of cardiac computed tomography in the PPE of competitive athletes, with a specific focus on its value for detecting congenital coronary anomalies and CAD in young and master athletes, respectively.
Discovery by metagenomics of a functional tandem repeat sequence that controls gene expression in bacteria
Authors: Suenaga Hikaru , Matsuzawa Tomohiko , Sahara Takehiko
Published: March 2022

The ability to degrade exogenous compounds is acquired by adaptive processes of microorganisms when they are exposed to compounds that are foreign to their existing enzyme systems. Previously, we reported that simultaneous point mutations and mobile genetic elements cause the evolution and optimization of the degradation systems for aromatic compounds. In the present study, we propose another element with this role—tandem repeats. The novel metagenomic tandem repeat (MTR) sequence T(G/A)ACATG(A/C)T was identified in the 5′-untranslated regions of catechol 2,3-dioxygenase (C23O)-encoding genes by metagenomic analysis. Recombinant Escherichia coli carrying a C23O gene with various numbers of MTRs exhibited increased C23O protein expression and enzyme activity compared with cells expressing the C23O gene without MTRs. Real-time reverse transcription PCR showed that changes in the numbers of MTRs affected the levels of detectable C23O mRNA in the E. coli host. Furthermore, the mRNAs transcribed from C23O genes containing various numbers of MTRs had longer half-lives than those transcribed from a C23O gene without MTRs. Thus, MTRs would affect the translation efficiency of the gene expression system. MTRs may change the expression levels of their downstream genes for adaptation to a fluctuating environment.
Connexinplexity: the spatial and temporal expression of connexin genes during vertebrate organogenesis
Authors: Lukowicz-Bedford Rachel M , Farnsworth Dylan R , Miller Adam C
Published: March 2022

Animal development requires coordinated communication between cells. The Connexin family of proteins is a major contributor to intercellular communication in vertebrates by forming gap junction channels that facilitate the movement of ions, small molecules, and metabolites between cells. Additionally, individual hemichannels can provide a conduit to the extracellular space for paracrine and autocrine signaling. Connexin-mediated communication is widely used in epithelial, neural, and vascular development and homeostasis, and most tissues likely use this form of communication. In fact, Connexin disruptions are of major clinical significance contributing to disorders developing from all major germ layers. Despite the fact that Connexins serve as an essential mode of cellular communication, the temporal and cell-type-specific expression patterns of connexin genes remain unknown in vertebrates. A major challenge is the large and complex connexin gene family. To overcome this barrier, we determined the expression of all connexins in zebrafish using single-cell RNA-sequencing of entire animals across several stages of organogenesis. Our analysis of expression patterns has revealed that few connexins are broadly expressed, but rather, most are expressed in tissue- or cell-type-specific patterns. Additionally, most tissues possess a unique combinatorial signature of connexin expression with dynamic temporal changes across the organism, tissue, and cell. Our analysis has identified new patterns for well-known connexins and assigned spatial and temporal expression to genes with no-existing information. We provide a field guide relating zebrafish and human connexin genes as a critical step toward understanding how Connexins contribute to cellular communication and development throughout vertebrate organogenesis.
Phage-mediated horizontal gene transfer and its implications for the human gut microbiome
Authors: Borodovich Tatiana , Shkoporov Andrey N , Ross R Paul , Hill Colin
Published: March 2022

Horizontal gene transfer (HGT) in the microbiome has profound consequences for human health and disease. The spread of antibiotic resistance genes, virulence, and pathogenicity determinants predominantly occurs by way of HGT. Evidence exists of extensive horizontal transfer in the human gut microbiome. Phage transduction is a type of HGT event in which a bacteriophage transfers non-viral DNA from one bacterial host cell to another. The abundance of tailed bacteriophages in the human gut suggests that transduction could act as a significant mode of HGT in the gut microbiome. Here we review in detail the known mechanisms of phage-mediated HGT, namely specialized and generalized transduction, lateral transduction, gene-transfer agents, and molecular piracy, as well as methods used to detect phage-mediated HGT, and discuss its potential implications for the human gut microbiome.
Nontransgenic Guinea Pig Strains Exhibit Hallmarks of Human Brain Aging and Alzheimer’s Disease
Authors: Wahl Devin , Moreno Julie A , Santangelo Kelly S , Zhang Qian , Afzali Maryam F , Walsh Maureen A , Musci Robert V , Cavalier Alyssa N , Hamilton Karyn L , LaRocca Thomas J
Published: March 2022

Older age is the primary risk factor for most chronic diseases, including Alzheimer’s disease (AD). Current preclinical models to study brain aging and AD are mainly transgenic and harbor mutations intended to mirror brain pathologies associated with human brain aging/AD (eg, by increasing production of the amyloid precursor protein, amyloid beta [Aβ], and/or phosphorylated tau, all of which are key pathological mediators of AD). Although these models may provide insight on pathophysiological processes in AD, none completely recapitulate the disease and its strong age-dependence, and there has been limited success in translating preclinical results and treatments to humans. Here, we describe 2 nontransgenic guinea pig (GP) models, a standard PigmEnTed (PET) strain, and lesser-studied Dunkin-Hartley (DH) strain, that may naturally mimic key features of brain aging and AD in humans. We show that brain aging in PET GP is transcriptomically similar to human brain aging, whereas older DH brains are transcriptomically more similar to human AD. Both strains/models also exhibit increased neurofilament light chain (NFL, a marker of neuronal damage) with aging, and DH animals display greater S100 calcium-binding protein B (S100β), ionized calcium-binding adapter molecule 1 (Iba1), and Aβ and phosphorylated tau—which are all important markers of neuroinflammation-associated AD. Collectively, our results suggest that both the PET and DH GP may be useful, nontransgenic models to study brain aging and AD, respectively.
Association Between Homocysteine, Frailty and Biomechanical Response of the CNS in NPH-Suspected Patients
Authors: Guillotin Sophie , Vallet Alexandra , Lorthois Sylvie , Cestac Philippe , Schmidt Eric , Delcourt Nicolas
Published: March 2022

Frailty is a geriatric syndrome that combines physiological decline, disruptions of homeostatic mechanisms across multiple physiologic systems and thus, strong vulnerability to further pathological stress. Previously, we provided the first evidence that increased risk of poor health outcomes, as quantified by a frailty index (FI), is associated with an alteration of the central nervous system (CNS) biomechanical response to blood pulsatility. In this study, we explored correlation between 14 biological parameters, the CNS elastance coefficient and FI. We included 60 adults (52–92 years) suspected of normal pressure hydrocephalus and presenting with markers of multiple coexisting brain pathologies, including Parkinson disease, Alzheimer disease, and vascular dementia. We showed that the homocysteine (Hcy) level was independently and positively associated with both the FI and the CNS elastance coefficient (adjusted R² of 10% and 6%). We also demonstrated that creatinine clearance and folate level were independently associated with Hcy level. Based on previous literature results describing the involvement of Hcy in endothelial dysfunction, glial activation, and neurodegeneration, we discuss how Hcy could contribute to the altered biomechanical response of the CNS and frailty.
The haplotype-resolved chromosome pairs of a heterozygous diploid African cassava cultivar reveal novel pan-genome and allele-specific transcriptome features
Authors: Qi Weihong , Lim Yi-Wen , Patrignani Andrea , Schläpfer Pascal , Bratus-Neuenschwander Anna , Grüter Simon , Chanez Christelle , Rodde Nathalie , Prat Elisa , Vautrin Sonia , Fustier Margaux-Alison , Pratas Diogo , Schlapbach Ralph , Gruissem Wilhelm
Published: March 2022

Background

Cassava (Manihot esculenta) is an important clonally propagated food crop in tropical and subtropical regions worldwide. Genetic gain by molecular breeding has been limited, partially because cassava is a highly heterozygous crop with a repetitive and difficult-to-assemble genome.

Findings

Here we demonstrate that Pacific Biosciences high-fidelity (HiFi) sequencing reads, in combination with the assembler hifiasm, produced genome assemblies at near complete haplotype resolution with higher continuity and accuracy compared to conventional long sequencing reads. We present 2 chromosome-scale haploid genomes phased with Hi-C technology for the diploid African cassava variety TME204. With consensus accuracy >QV46, contig N50 >18 Mb, BUSCO completeness of 99%, and 35k phased gene loci, it is the most accurate, continuous, complete, and haplotype-resolved cassava genome assembly so far. Ab initio gene prediction with RNA-seq data and Iso-Seq transcripts identified abundant novel gene loci, with enriched functionality related to chromatin organization, meristem development, and cell responses. During tissue development, differentially expressed transcripts of different haplotype origins were enriched for different functionality. In each tissue, 20–30% of transcripts showed allele-specific expression (ASE) differences. ASE bias was often tissue specific and inconsistent across different tissues. Direction-shifting was observed in <2% of the ASE transcripts. Despite high gene synteny, the HiFi genome assembly revealed extensive chromosome rearrangements and abundant intra-genomic and inter-genomic divergent sequences, with large structural variations mostly related to LTR retrotransposons. We use the reference-quality assemblies to build a cassava pan-genome and demonstrate its importance in representing the genetic diversity of cassava for downstream reference-guided omics analysis and breeding.

Conclusions

The phased and annotated chromosome pairs allow a systematic view of the heterozygous diploid genome organization in cassava with improved accuracy, completeness, and haplotype resolution. They will be a valuable resource for cassava breeding and research. Our study may also provide insights into developing cost-effective and efficient strategies for resolving complex genomes with high resolution, accuracy, and continuity.
Environmental effects and seismogenic source characterization of the December 2020 earthquake sequence near Petrinja, Croatia
Authors: Baize S , Amoroso S , Belić N , Benedetti L , Boncio P , Budić M , Cinti F R , Henriquet M , Jamšek Rupnik P , Kordić B , Markušić S , Minarelli L , Pantosti D , Pucci S , Špelić M , Testa A , Valkaniotis S , Vukovski M , Atanackov J , Barbača J , Bavec M , Brajkovič R , Brčić V , Caciagli M , Celarc B , Civico R , De Martini P M , Filjak R , Iezzi F , Moulin A , Kurečić T , Métois M , Nappi R , Novak A , Novak M , Pace B , Palenik D , Ricci T
Published: March 2022

On 29 December 2020, a shallow earthquake of magnitude Mw 6.4 struck northern Croatia, near the town of Petrinja, more than 24 hr after a strong foreshock (ML 5). We formed a reconnaissance team of European geologists and engineers, from Croatia, Slovenia, France, Italy and Greece, rapidly deployed in the field to map the evidence of coseismic environmental effects. In the epicentral area, we recognized surface deformation, such as tectonic breaks along the earthquake source at the surface, liquefaction features (scattered in the fluvial plains of Kupa, Glina and Sava rivers), and slope failures, both caused by strong motion. Thanks to this concerted, collective and meticulous work, we were able to document and map a clear and unambiguous coseismic surface rupture associated with the main shock. The surface rupture appears discontinuous, consisting of multi-kilometre en échelon right stepping sections, along a NW–SE striking fault that we call the Petrinja-Pokupsko Fault. The observed deformation features, in terms of kinematics and trace alignments, are consistent with slip on a right lateral fault, in agreement with the focal solution of the main shock. We found mole tracks, displacement on faults affecting natural features (e.g. drainage channels), scarplets and more frequently breaks of anthropogenic markers (roads, fences). The surface rupture is observed over a length of ∼13 km from end-to-end, with a maximum displacement of 38 cm, and an average displacement of ∼10 cm. Moreover, the liquefaction extends over an area of nearly 600 km2 around the epicentre. Typology of liquefaction features include sand blows, lateral spreading phenomenon along the road and river embankments, as well as sand ejecta of different grain size and matrix. Development of large and long fissures along the fluvial landforms, current or ancient, with massive ejections of sediments is pervasive. These features are sometimes accompanied by small horizontal displacements. Finally, the environmental effects of the earthquake appear to be reasonably consistent with the usual scaling relationships, in particular the surface faulting. This rupture of the ground occurred on or near traces of a fault that shows clear evidence of Quaternary activity. Further and detailed studies will be carried out to characterize this source and related faults in terms of future large earthquakes potential, for their integration into seismic hazard models.