bluuebunny/crossref_metadata_2025 huggingface dataset:
When adaptive radiations collide: Different evolutionary trajectories between and within island and mainland lizard clades
Authors: Patton Austin H. , Harmon Luke J. , del Rosario Castañeda María , Frank Hannah K. , Donihue Colin M. , Herrel Anthony , Losos Jonathan B.
Published: October 2021

Significance

Isolated and infrequently colonized, islands harbor many of nature’s most renowned evolutionary radiations. Despite this evolutionary exuberance, island occupation has long been considered irreversible: The much tougher competitive and predatory milieu on mainlands prevents colonization, much less evolutionary diversification, from islands to continents. To test these postulates, we examined neotropicalAnolislizards, asking what happens when mainland and island evolutionary radiations collide. Far from being a dead end, we show that island-to-mainland colonization seeded an extensive radiation that achieved its ecomorphological disparity in ways distinct from their island ancestors. Moreover, when the incumbent and island-derived radiations collided, the ensuing interactions favored the latter, together highlighting a persistent role of both historical contingency and determinism in adaptive radiation.
Density-dependent mating behaviors reduce male mating harassment in locusts
Authors: Maeno Koutaro Ould , Piou Cyril , Ould Ely Sidi , Ould Mohamed Sid’Ahmed , Jaavar Mohamed El Hacen , Ghaout Saïd , Babah Ebbe Mohamed Abdallahi Ould
Published: October 2021

Significance

In animal societies, social life often generates male mating harassment. How do communal animals manage such conflicts without escalating antagonistic relationships? In the Sahara Desert, we studied the mating system of gregarious-behaving desert locusts, the world’s most destructive locust. Despite being widespread and abundant during plagues, its populations are otherwise difficult to access, and its reproductive behaviors in the field are understudied. We show that female locusts behaviorally overcome the costs of male mating harassment: females occupy separate sites before and after mating. Only females with ripe ovaries arrive at male-biased lekking groups. Hence, substantial social conflicts can be simply managed by behaviors. These findings invite to explore the evolutionary hypotheses behind lekking with a density-dependent plastic species.
Development of an entirely plasmid-based reverse genetics system for 12-segmented double-stranded RNA viruses
Authors: Nouda Ryotaro , Minami Shohei , Kanai Yuta , Kawagishi Takahiro , Nurdin Jeffery A. , Yamasaki Moeko , Kuwata Ryusei , Shimoda Hiroshi , Maeda Ken , Kobayashi Takeshi
Published: October 2021

Significance

Coltiviruses, including important pathogens such as Colorado tick fever virus in humans, have a genome comprising 12 segments of double-stranded (ds) RNA. However, due to the lack of a reverse genetics system, the molecular mechanisms of coltivirus biology are largely unknown. Here, we established an entirely plasmid-based reverse genetics system for Tarumizu tick virus, a member of the genus
Coltivirus
, isolated from the brain of a dead raccoon dog. Recombinant wild-type and mutant viruses were generated from cloned complementary DNAs. This is a report of a reverse genetics system for
Reoviridae
viruses harboring a genome comprising 12 segments of dsRNA. This technology provides opportunities for understanding the mechanisms of replication and pathogenesis of viruses within the genus
Coltivirus
.
Vasoactive intestinal peptide promotes host defense against enteric pathogens by modulating the recruitment of group 3 innate lymphoid cells
Authors: Yu Hong Bing , Yang Hyungjun , Allaire Joannie M. , Ma Caixia , Graef Franziska A. , Mortha Arthur , Liang Qiaochu , Bosman Else S. , Reid Gregor S. , Waschek James A. , Osborne Lisa C. , Sokol Harry , Vallance Bruce A. , Jacobson Kevan
Published: October 2021

Significance

Group 3 innate lymphoid cells enriched in the gut mediate host resistance against intestinal pathogens. Their function and development can be regulated by diverse factors, including neuropeptides secreted by the enteric nervous system. We show that the neuropeptide vasoactive intestinal peptide (VIP) promotes the recruitment of these innate lymphoid cells and other immune cells to the gut through a receptor. Mice lacking VIP or its receptor were highly susceptible to an enteric pathogen infection. Replenishing the innate lymphoid cells or their secreted products into these mice was able to partially or fully restore host resistance to the infection. Thus, the enteric nervous system, through VIP, regulates the recruitment of innate lymphoid cells to the gut, offering protection against enteric pathogens.
Roles of verb and construction cues
Authors: Shin Gyu-Ho , Kim Hyunwoo
Published: October 2021

This study investigates how speakers of English and Korean, two typologically distinct languages, derive information from a verb and a construction to achieve sentence comprehension. In a sentence-sorting task, we manipulated verb semantics (real versus nonce) in each language. The results showed that participants from both languages were less inclined to sort sentences by a verb cue when the lexical-semantic information about a verb was obscured (i.e., nonce verb). In addition, the Korean-speaking participants were less likely affected by the verb semantics conditions than the English-speaking participants. These findings suggest the role of an argument structure construction in sentence comprehension as a co-contributor of sentence meaning, supporting the constructionist approach. The findings also imply language-specific mechanisms of sentence comprehension, contingent upon the varied impact of a verb on sentence meaning in English and Korean.
Cultural conceptualisations ofloong(龙) in Chinese idioms
Authors: Wen Xu , Chen Chuanhong
Published: October 2021

This study investigates the abundant metaphorical meanings of the termloong(‘dragon’) in Chinese idioms and the cognitive and cultural factors that influence those meanings from the perspective of Cultural Linguistics. To this end, we present a systematic categorisation of the idiomatic expressions involving the termloongin Mandarin Chinese based on three conceptual metaphors:a human being is a loong, a concrete entity is a loong, andan abstract object is a loong. We then elaborate on the cultural conceptualisations ofloongfrom three perspectives: cultural schemas, cultural categories, and cultural metaphors. The results of the study show how the metaphorical conceptualisations ofloongare profoundly influenced by Chinese culture. The resulting study is intended to add to the pool of studies which lend support to the view that a fine-grained study of the metaphors of a particular culture and their linguistic realisation can shed light on how culture influences human cognition. Finally, the study calls for a clearer integration of cultural approaches into conceptual metaphor theory and it explores some possibilities in this regard.
Photoreflectance studies of temperature and hydrostatic pressure dependencies of direct optical transitions in BGaAs alloys grown on GaP
Authors: Kopaczek J , Dybała F , Zelewski S J , Sokołowski N , Żuraw W , McNicholas K M , El-Jaroudi R H , White R C , Bank S R , Kudrawiec R
Published: October 2021

BGaAs layers with boron concentrations of 4.1%, 7.4%, and 12.1% are grown by molecular beam epitaxy on a GaP substrate and studied by optical absorption and photoreflectance (PR) spectroscopy with both temperature and hydrostatic pressure dependence. The direct optical transitions from the bands composing the valence band—namely heavy-hole, light-hole, and spin–orbit split-off—to the conduction band are clearly observed in the PR spectra. For the abovementioned optical transitions, their temperature dependencies are obtained in the range from 20 K to 300 K, and analyzed by Varshni and Bose–Einstein relations. Furthermore, the BGaAs alloys are also studied with hydrostatic pressure up to ∼18 kbar, revealing pressure coefficients of direct optical transitions. The obtained results are discussed within the framework of the band anticrossing model and chemical trends.
Mode engineering of semiconductor lasers with vertical periodic layered structures
Authors: Zhang Jing , Ma Xiaolong , Zhou Xuyan , Liu Anjin , Zheng Wanhua
Published: October 2021

High-power and low-divergence semiconductor lasers are useful in light detection and ranging, as well as material processing and so on. In this paper, an efficient approach is presented to explain the physics of mode selection in semiconductor lasers with vertical periodic layers for high power and low vertical beam divergence. The transmission matrix method is used to obtain the allowed band and forbidden band of the vertical periodic layered structure, and the band diagram of the layered structure of the semiconductor laser. The fundamental mode of the layered structure of the semiconductor laser lies in the forbidden band of the vertical periodic layered structure. Tapered lasers based on the designed layered structure are fabricated and can achieve an output power of 2.45 W. The measured vertical divergence angle of the tapered laser is below 10°, consistent well with the calculated result of 9.5°.
Magnetic gradiometry using frequency-domain filtering
Authors: Ream Jodie B , Weiss Benjamin P , Oran Rona , Raymond Carol A , Polanskey Carol A , Wenkert Daniel D , Elkins-Tanton Linda T , Hart Richard A , Russell Christopher T , Merayo Jose M G
Published: October 2021

Accurate measurements of ambient planetary and interplanetary magnetic fields using spacecraft magnetometers typically require accounting for interfering magnetic fields generated by the flight system (FS). The most common method for removing FS-generated time-variable magnetic fields is narrow-band and low-pass filtering of magnetic field data in the frequency domain. However, if fluctuations in the ambient field contain frequencies overlapping those in the FS field, it can be difficult to construct a filter that will not affect both signals. Here we present an alternate method for removing FS time-variable signatures from magnetic field measurements. For spacecraft that make use of a magnetic gradiometer (i.e. with two or more instruments on a boom at different distances from the center of the spacecraft), the dominant frequencies in the FS field can be identified using spectra of the differenced field components. The amplitudes of the FS field at those frequencies can then be suppressed without removing spectral peaks present in the ambient field. We demonstrate the successful application of this method, referred to as gradiometry peak suppression, both to modeled data sets and to 128 Hz Venus Express magnetometer data.
Models for sensing by nanowire networks: application to organic vapour detection by multiwall carbon nanotube—DNA films
Authors: Ali Shams B , Oshido Atsinafe B , Houlton Andrew , Horrocks Benjamin R
Published: October 2021

Electronic sensors for volatile organic compounds have been prepared by drop-casting dispersions of multi-wall carbon nanotubes (MWCNTs) in aqueous solutions of λ-DNA onto Pt microband electrodes. The MWCNTs themselves show a metal-like temperature dependence of the conductance, but the conductance of DNA/MWCNT composites has an activated component that corresponds to inter-tube tunneling. The resistance of the composite was modelled by a series combination of a term linear in temperature for the nanotubes and a stretched exponential form for the inter-tube junctions. The resistance may increase or decrease with temperature according to the composition and may be tuned to be almost temperature-independent at 67% by mass of DNA. Upon exposure to organic vapours, the resistance of the composites increases and the time-dependence of this signal is consistent with diffusion of the vapour into the composite. The fractional change in resistance at steady-state provides an analytical signal with a linear calibration and the presence of DNA enhances the signal and adjusts the selectivity in favour of polar analytes. The temperature dependence of the signal is determined by the enthalpy of adsorption of the analyte in the inter-tube junctions and may be satisfactorily modelled using the Langmuir isotherm. Temperature and pressure-dependent studies indicate that neither charge injection by oxidation/reduction of the analyte nor condensation of analyte on the device is responsible for the signal. We suggest that the origin of the sensing response is an adsorption of the analyte in the inter-tube regions that modulates the tunneling barriers. This suggests a general route to tuning the selectivity of MWCNT gas sensors using non-conductive polymers of varying chemical functionality.
Block copolymers as (single-ion conducting) lithium battery electrolytes
Authors: Mayer Alexander , Steinle Dominik , Passerini Stefano , Bresser Dominic
Published: October 2021

Solid-state batteries are considered the next big step towards the realization of intrinsically safer high-energy lithium batteries for the steadily increasing implementation of this technology in electronic devices and particularly, electric vehicles. However, so far only electrolytes based on poly(ethylene oxide) have been successfully commercialized despite their limited stability towards oxidation and low ionic conductivity at room temperature. Block copolymer (BCP) electrolytes are believed to provide significant advantages thanks to their tailorable properties. Thus, research activities in this field have been continuously expanding in recent years with great progress to enhance their performance and deepen the understanding towards the interplay between their chemistry, structure, electrochemical properties, and charge transport mechanism. Herein, we review this progress with a specific focus on the block-copolymer nanostructure and ionic conductivity, the latest works, as well as the early studies that are fr"equently overlooked by researchers newly entering this field. Moreover, we discuss the impact of adding a lithium salt in comparison to single-ion conducting BCP electrolytes along with the encouraging features of these materials and the remaining challenges that are yet to be solved.
Quantum conductors formation and resistive switching memory effects in zirconia nanotubes
Authors: Vokhmintsev Alexander , Petrenyov Ilya , Kamalov Robert , Weinstein Ilya
Published: October 2021

The prospects of the development of non-volatile memory elements that involve memristive metal-dielectric-metal sandwich structures are due to the possibility of reliably implementing sustained functional states with quantized conductance. In the present paper, we have explored the properties of Zr/ZrO2/Au memristors fabricated based on an anodic zirconia layer that consists of an ordered array of vertically oriented non-stoichiometric nanotubes with an outer diameter of 30 nm. The operational stability of the designed memory devices has been analyzed in unipolar and bipolar resistive switching modes. The resistance ratio ≥105 between high-resistance (HRS) and low-resistance (LRS) states has been evaluated. It has been found that the LRS conductivity is quantized over a wide range with a fundamental minimum of 0.5G
0 = 38.74 μS due to the formation of quantum conductors based on oxygen vacancies (VO). For Zr/ZrO2/Au memristors, resistive switching mechanisms to be sensitive to the migration of VO in an applied electric field have been proposed. It has been shown that the ohmic type and space-charge-limited conductivities are realized in the LRS and HRS, respectively. Besides, we have offered a brief review of parameters for functional metal/zirconia/metal nanolayered structures to create effective memristors with multiple resistive states and a high resistance ratio.
Applications of nanomagnets as dynamical systems: I
Authors: Rana Bivas , Mondal Amrit Kumar , Bandyopadhyay Supriyo , Barman Anjan
Published: October 2021

When magnets are fashioned into nanoscale elements, they exhibit a wide variety of phenomena replete with rich physics and the lure of tantalizing applications. In this topical review, we discuss some of these phenomena, especially those that have come to light recently, and highlight their potential applications. We emphasize what drives a phenomenon, what undergirds the dynamics of the system that exhibits the phenomenon, how the dynamics can be manipulated, and what specific features can be harnessed for technological advances. For the sake of balance, we point out both advantages and shortcomings of nanomagnet based devices and systems predicated on the phenomena we discuss. Where possible, we chart out paths for future investigations that can shed new light on an intriguing phenomenon and/or facilitate both traditional and non-traditional applications.
Molecular dynamics investigations of the size effects on mechanical properties and deformation mechanism of amorphous and monocrystalline composite AlFeNiCrCu high-entropy alloy nanowires
Authors: Niu Yihan , Zhao Dan , Zhu Bo , Wang Shunbo , Wang Zhaoxin , Zhao Hongwei
Published: October 2021

The atomic models of amorphous and monocrystalline composite AlFeNiCrCu high-entropy alloy nanowires were established via the molecular dynamics method. The effects of amorphous structure thickness on mechanical properties and deformation mechanism were investigated by applying tensile and compressive loads to the nanowires. As the thickness of amorphous structures increases, the tensile yield strength decreases, and the asymmetry between tension and compression decreases. The tensile deformation mechanism transforms from the coupling interactions between stacking faults in crystal structures and uniform deformation of amorphous structures to the individual actions of uniform deformation of amorphous structures. During the tensile process, the nanowires necking appears at amorphous structures, and the thinner amorphous structures, the more prone to necking. The compressive deformation mechanism is the synergistic effects of twins and SFs in crystal structures and uniform deformation of amorphous structures, which is irrelevant to amorphous structure thickness. Remarkably, amorphous structures transform into crystal structures in the amorphous and monocrystalline composite nanowires during the compressive process.
Self-focusing of a spatially modulated beam within the paraxial complex geometrical optics framework in low-density plasmas
Authors: Ruocco A , Duchateau G , Tikhonchuk V T
Published: October 2021

Accurate modelling of ponderomotive laser self-focusing may represent a key for the success of inertial confinement fusion, especially within the shock ignition approach. From a numerical point of view, implementation of a paraxial complex geometrical optics (PCGO) method has improved the performance of the hydrodynamics code CHIC, but (1) overestimating ponderomotive speckle self-focusing in reduced two-dimensional geometry, and (2) not accounting for speckle intensity statistics. The first issue was addressed in our previous work (Ruocco et al 2019 Plasma Phys. Control. Fusion
61 115009). Based on those results, here we propose a novel PCGO scheme for modelling spatially modulated laser beams by (1) creating Gaussian speckles, and (2) emulating the realistic speckle intensity statistics. Self-focusing of spatially modulated beams in a homogeneous stationary plasma with this method is studied. This investigation evidences that plasma smoothing does not reduce the speckle intensity enhancement at long time scales when the average beam intensity is twice above the speckle critical intensity. Comparison against electromagnetic simulations confirms that this approach improves the description of self-focusing of high-intensity speckles within the PCGO model.
An efficient low-temperature triethylamine gas sensor based on 2D ultrathin SnO2 nanofilms
Authors: Liu Yuchang , Liu Hongjie , Hu Anjie , Wei Yingmei , Ou Wenchao , Deng Xianwang , Wang Shaopeng , Yu Kefu
Published: October 2021

The quest to develop inexpensive chemical sensing materials that are energy-efficient, portable, and with efficient performance lies at the center of next-generation sensor development. Owing to their low cost, easy preparation, high response, and smooth integration with electronic circuits, metal oxide semiconductors have received particular attention. Yet, metal oxide semiconductor based sensors often suffer from high power consumption due to their high operating temperature, which hinders them from practical applications. To solve this problem, herein, we proposed ultrathin sub-4 nm SnO2 films synthesized by a facile tunable hydrothermal method. Benefiting immensely from its two-dimensional anisotropic nature, the proposed SnO2 ultra-thin film exhibits a large specific area of 94.41 m2 g−1 and possesses surface oxygen vacancies. The obtained sample was practically applied as a gas sensor; the results indicate that the ultra-thin SnO2 film based sensor exhibits the highest sensitivity to triethylamine (19.2 at 100 ppm), outstanding repeatability, and excellent sensing selectivity at a low working temperature of 150 °C.
Design, modeling and testing of a new compressive amplifier structure for piezoelectric harvester
Authors: Long Su Xian , Khoo Shin Yee , Ong Zhi Chao , Soong Ming Foong
Published: October 2021

In recent years, harnessing electrical energy from mechanical vibration by using a piezoelectric energy harvester (PEH) has attracted much attention from researchers. This sustainable energy harvester is useful for wireless sensor network, where a replacement or replenishment of an energy source such as a battery is impractical. From previous studies, the amount of energy generated by the PEH is very limited even in a high force environment. To solve this issue, mechanical amplifier structure such as Cymbal structure is implemented to amplify the tensile loading force towards the PEH. In terms of the material strength perspective, this performance can be further enhanced by using a compressive-type mechanical amplifier structure, as the compressive yield strength of piezoelectric material is much higher than its tensile yield strength. In this study, a compressive structural design which is named as Hull structure is proposed. Several techniques included analytical model analysis, finite element analysis (FEA), and experimental testing have been used to evaluate its performance. It shows a force amplification factor of 9.72 at 6° through the analytical model. From the FEA result, the proposed Hull structure shows great potential in enhancing the power output of 11.34 mW, which is 3.08 times larger than the benchmarking Tensile Cymbal structure. It also shows 5.28 times greater output voltage than the benchmark case in the experiment. Besides, it has a great advantage of providing a wider area for excitation loading force which increases the PEH’s load capacity and suitable for the vehicular excitation application.
Electrical properties of NbN/NbN
x
/NbN Josephson junctions
Authors: Zhang Lu , Yan Kaixin , Tao Yuanhe , Zhong Yulong , Shi Jiasheng , Zeng Junwen , Shi Weifeng , Wu Ling , Wang Huiwu , Peng Wei , Chen Lei , Wang Zhen
Published: October 2021

In this work, we report the electrical properties of NbN internally shunted Josephson junctions with NbN
x
barriers. Cross-sectional scanning transmission electron microscopy analysis shows that all layers have the same cubic structure; NbN/NbN
x
/NbN trilayers were epitaxially grown on MgO substrates. The resistivity of the NbN
x
films could be varied in the range of 1–104 mΩ cm by controlling both the N2 partial pressure and the deposition time during reactive sputtering. The temperature dependence of the critical current density (J
c) and characteristic voltage (I
c
R
n) of the junctions with different barrier resistivities were measured for various barrier thicknesses. For the 10 nm-thick NbN
x
layer with resistivities of 73.44, 385.72, and 711 mΩ cm, the coherence length of the barrier was determined to be 5.55 ± 0.07, 4.88 ± 0.06, and 1.40 ± 0.13 nm, respectively, corresponding to carrier diffusion rates of 2.741 ± 0.004, 1.211 ± 0.002, and 0.008 ± 0.001 cm2 s−1, respectively. Thus, the reduction in barrier resistivity leads to a larger coherence length and a faster diffusion rate, which will further increase the J
c and I
c
R
n of the junction. By adjusting the barrier resistivity and thickness, the J
c of the junction can be easily tuned over more than four orders of magnitude, and an I
c
R
n value of 0.97 ± 0.07 mV was obtained at 10 K. The results indicate that the all-NbN self-shunt junction is a promising candidate in high-speed and high-temperature applications.
Vortex dynamics in amorphous MoSi superconducting thin films
Authors: Liu Zhengyuan , Luo Bingcheng , Zhang Labao , Hou Boyu , Wang Danyang
Published: October 2021

Vortex dynamics in superconductors have received a great deal of attention from both fundamental and applied researchers over the past few decades. Because of their critical role in the energy relaxation process of type-II superconductors, vortex dynamics have been deemed a key factor for the emerging superconducting devices, but the effect of irradiation on vortex dynamics remains unclear. With the support of electrical transport measurements under external magnetic fields and irradiation, the photon effect on vortex dynamics in amorphous MoSi (a-MoSi) superconducting thin films is investigated in this work. The magnetic-field-dependent critical vortex velocity v*
derived from the Larkin–Ovchinnikov (LO) model is not significantly affected by irradiation. However, vortex depinning is found to be enhanced by photon-induced reduction in the potential barrier, which mitigates the adverse effect of film inhomogeneity on superconductivity in the a-MoSi thin films. A thorough understanding of the vortex dynamics in a-MoSi thin films under the effect of external stimuli is of paramount importance for both further fundamental research in this area and the optimization of future superconducting devices.
Dependency of hysteretic loss on speed and tilt in a rotating superconducting magnetic bearing
Authors: Espenhahn Tilo , Sparing Maria , Berger Anne , Nielsch Kornelius , Hühne Ruben
Published: October 2021

Superconducting magnetic bearings enable friction-free rotation, which is beneficial for different applications. Whereas mechanical losses are drastically reduced, additional hysteretic losses might be generated as for example by a process-related tilt of the field-cooled permanent magnet of the superconducting bearing. We designed a caloric measurement setup with a resolution down to 5 mW in order to study such losses in more detail. Therefore, a field-cooled magnet ring is deliberately tilted up to 3° before it rotates with a speed of up to 5000 rpm above the superconducting ring. The generated losses inside the superconductor lead to an increased evaporation rate in the attached liquid nitrogen bath, which in turn results to a measurable volume flow. The determined losses increase almost linear with speed, whereas an exponential increase was observed for the tilt angle. The results were confirmed by 2D simulations using a two-component model leading to similar dependencies for the hystertic losses on speed and tilt.
Coral: a web-based visual analysis tool for creating and characterizing cohorts
Authors: Adelberger Patrick , Eckelt Klaus , Bauer Markus J , Streit Marc , Haslinger Christian , Zichner Thomas
Published: October 2021

A main task in computational cancer analysis is the identification of patient subgroups (i.e. cohorts) based on metadata attributes (patient stratification) or genomic markers of response (biomarkers). Coral is a web-based cohort analysis tool that is designed to support this task: Users can interactively create and refine cohorts, which can then be compared, characterized and inspected down to the level of single items. Coral visualizes the evolution of cohorts and also provides intuitive access to prevalence information. Furthermore, findings can be stored, shared and reproduced via the integrated session management. Coral is pre-loaded with data from over 128 000 samples from the AACR Project GENIE, the Cancer Genome Atlas and the Cell Line Encyclopedia.

Availability and implementation

Coral is publicly available at https://coral.caleydoapp.org. The source code is released at https://github.com/Caleydo/coral.

Supplementary information

Supplementary data are available at Bioinformatics online.
Imbalanced basal ganglia connectivity is associated with motor deficits and apathy in Huntington’s disease
Authors: Nair Akshay , Razi Adeel , Gregory Sarah , Rutledge Robb B , Rees Geraint , Tabrizi Sarah J
Published: October 2021

The gating of movement depends on activity within the cortico-striato-thalamic loops. Within these loops, emerging from the cells of the striatum, run two opponent pathways—the direct and indirect basal ganglia pathways. Both are complex and polysynaptic, but the overall effect of activity within these pathways is thought to encourage and inhibit movement, respectively. In Huntington’s disease, the preferential early loss of striatal neurons forming the indirect pathway is thought to lead to disinhibition, giving rise to the characteristic motor features of the condition. But early Huntington’s disease is also associated with apathy, a loss of motivation and failure to engage in goal-directed movement. We hypothesized that in Huntington’s disease, motor signs and apathy may be selectively correlated with indirect and direct pathway dysfunction, respectively.

We used spectral dynamic casual modelling of resting-state functional MRI data to model effective connectivity in a model of these cortico-striatal pathways. We tested both of these hypotheses in vivo for the first time in a large cohort of patients with prodromal Huntington’s disease. Using an advanced approach at the group level we combined parametric empirical Bayes and Bayesian model reduction procedures to generate a large number of competing models and compare them using Bayesian model comparison. With this automated Bayesian approach, associations between clinical measures and connectivity parameters emerge de novo from the data.

We found very strong evidence (posterior probability > 0.99) to support both of our hypotheses. First, more severe motor signs in Huntington’s disease were associated with altered connectivity in the indirect pathway components of our model and, by comparison, loss of goal-direct behaviour or apathy, was associated with changes in the direct pathway component.

The empirical evidence we provide here demonstrates that imbalanced basal ganglia connectivity may play an important role in the pathogenesis of some of commonest and disabling features of Huntington’s disease and may have important implications for therapeutics.
Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Dose, Infection, and Disease Outcomes for Coronavirus Disease 2019 (COVID-19): A Review
Authors: Brosseau Lisa M , Escandón Kevin , Ulrich Angela K , Rasmussen Angela L , Roy Chad J , Bix Gregory J , Popescu Saskia V , Moore Kristine A , Osterholm Michael T
Published: October 2021

The relationship between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) dose, infection, and coronavirus disease 2019 (COVID-19) outcomes remains poorly understood. This review summarizes the existing literature regarding this issue, identifies gaps in current knowledge, and suggests opportunities for future research. In humans, host characteristics, including age, sex, comorbidities, smoking, and pregnancy, are associated with severe COVID-19. Similarly, in animals, host factors are strong determinants of disease severity, although most animal infection models manifest clinically with mild to moderate respiratory disease. The influence of variants of concern as it relates to infectious dose, consequence of overall pathogenicity, and disease outcome in dose–response remains unknown. Epidemiologic data suggest a dose–response relationship for infection contrasting with limited and inconsistent surrogate-based evidence between dose and disease severity. Recommendations include the design of future infection studies in animal models to investigate inoculating dose on outcomes and the use of better proxies for dose in human epidemiology studies.
Safety and Efficacy of Levamisole in Loiasis: A Randomized, Placebo-controlled, Double-blind Clinical Trial
Authors: Campillo Jérémy T , Bikita Paul , Hemilembolo Marlhand , Louya Frédéric , Missamou François , Pion Sébastien D S , Boussinesq Michel , Chesnais CédricB
Published: October 2021

Background

Individuals with high microfilarial densities (MFDs) of Loa loa are at risk of developing serious adverse events (SAEs) after ivermectin treatment. Pretreatment with drugs progressively reducing Loa MFDs below the risk threshold might help prevent these SAEs. We assessed the safety and efficacy of levamisole for this purpose.

Methods

A double-blind, randomized, placebo-controlled, MFD-ascending trial was conducted in the Republic of the Congo. Participants were treated in 3 cohorts defined by pretreatment MFD and levamisole dose (cohort 1: 1.0kg and 1.5mg/kg; cohorts 2 and 3: 2.5mg/kg). Safety outcomes were occurrence of SAE and adverse event frequency during the first week. The efficacy outcomes were MFD reduction from baseline and proportions of individuals with at least 40% and 80% MFD reduction at day 2 (D2), D7, and D30.

Results

The 2 lowest doses (1.0mg/kg and 1.5mg/kg) caused no SAEs but were ineffective. Compared with placebo, 2.5mg/kg levamisole caused more mild adverse events (10/85 vs. 3/85, P=.018), a higher median reduction from baseline to D2 (-12.9% vs. +15.5%, P<.001), D7 (-4.9% vs. +18.7%, P<.001), and D30 (-0.5% vs. +13.5%, P=.036) and a higher percentage of participants with >40% MFD reduction at D2 (17.5% vs. 1.2%, P<.001), D7 (11.8% vs. 6.3%, P=.269), and D30 (18.5% vs. 9.6%, P=.107).

Conclusions

A single 2.5mg/kg levamisole dose induces a promising transient reduction in Loa loa MFDs and should encourage testing different regimens.
Low diversity, little genetic structure but no inbreeding in a high-density island endemic pit-viperGloydius shedaoensis
Authors: Wen Guannan , Jin Long , Wu Yayong , Wang Xiaoping , Fu Jinzhong , Qi Yin
Published: October 2021

Island species and their ecosystems play an important role in global biodiversity preservation, and many vulnerable island species are conservation priorities. Although insular habitat likely facilitates the species diversification process, it may also aggravate the fragility of these species with high risk of inbreeding. The Shedao pit-viper Gloydius shedaoensis is an island endemic species with an extremely high population density, which has been categorized as vulnerable in the IUCN (International Union for the Conservation of Nature and Natural Resources) Red List. We collected 13,148 SNP (Single Nucleotide Polymorphism) from across its genome and examined its genetic diversity and demographic history. The Shedao pit-viper has a low genetic diversity but shows no sign of inbreeding. Furthermore, population genetic structure analysis, including the neighbor-joining tree, principal coordinate analysis, clustering, and spatial autocorrelation, revealed a general lack of spatial structure. Only the isolation by distance residues suggested a weak patchiness. Overall, the population is nearly panmictic and gene flow is evenly distributed across the island. A large number of individuals, small size of the island, and the lack of population structure likely all contribute to the lack of inbreeding in this species. We also detected signs of male-biased dispersal, which likely is another inbreeding avoidance strategy. Historical demographic analysis suggested that the historical population size and distribution of the species are much larger than their current ones. The multiple transgressive–regressive events since the Late Pleistocene are likely the main cause of the population size changes. Taken together, our results provide a basic scientific foundation for the conservation of this interesting and important species.
How effective is cryoablation in the treatment of atrial fibrillation?
Authors: Penela Diego , Cappato Riccardo
Published: October 2021

Pulmonary vein isolation is the standard for atrial fibrillation ablation. Although the most commonly applied energy source is radiofrequency (RF), cryoablation has rapidly evolved as a powerful one-shot tool, particularly after the introduction of the second-generation catheter, gaining widespread use in recent years. The efficacy in maintaining sinus rhythm after a first ablative procedure is ∼70–80%, and the randomization studies comparing cryoablation to RF have not been able to reveal significant differences up to now. Although different baseline characteristics may influence the efficacy of cryoablation, we are not yet able to distinguish which patients may benefit from a personalized choice of ablative source. Regarding safety, cryoballoon ablation appears to be associated with a lower rate of pericardial effusion and cardiac tamponade, mainly due to the lack of risk of overheating. The other side of the coin is a higher incidence of phrenic nerve damage, which occurs in 1–2% of procedures. In conclusion, we do not yet have definitive data to affirm the superiority of the RF technique over that of cryoablation. The choice of energy source currently depends on the availability of the centre and on the experience of the operator.
New players in the treatment of hypercholesterolaemia: focus on bempedoic acid and inclisiran
Authors: Ruscica Massimiliano , Sirtori Cesare Riccardo , Ferri Nicola , Corsini Alberto
Published: October 2021

Dyslipidaemias and in particular elevated plasma low-density lipoprotein cholesterol (LDL-C) levels are major risk factors for atherosclerotic cardiovascular disease (ASCVD). Indeed, the more LDL-C is reduced the larger will be the ASCVD risk reduction. Although statins represent the first-line intervention to reduce the atherosclerotic burden driven by raised levels of LDL-C, adherence is not optimal and most patients do not follow guidelines and recommended doses. Thus, to achieve optimal LDL-C goals, especially in very high-risk patients, there is a need for new and safe agents, more tolerable than statins with low risk of myalgia. Thus, the present review will address the most recent clinical trials with bempedoic acid and inclisiran. Bempedoic acid is an oral drug acting at a biochemical step preceding hydroxymethylglutaryl-CoA reductase and not associated with muscular side effects. Inclisiran, the first-in-class small interfering RNA-based approach, has the ability to effectively reduce LDL-C by inhibiting the hepatic synthesis of proprotein convertase subtilisin/kexin type 9, with the advantage of requiring subcutaneous of a single dose on Day 1, Day 90, and every 6 months thereafter.
Prevention of ischaemic events in subjects with polydistrict vascular disease
Authors: Patti Giuseppe , Ghiglieno Chiara
Published: October 2021

The incidence of new cardiovascular events in patients with chronic coronary syndrome remains high, particularly in the presence of concomitant high thrombotic risk factors (diabetes mellitus, renal failure, multivessel coronary artery disease, multiple district atherosclerosis, recurrent events, heart failure). The risk of such recurrent events can be reduced by implementing various strategies, which include careful individual stratification of ischaemic and haemorrhagic risk and the choice of the most appropriate antithrombotic therapy for the individual patient, also by combining aspirin with a second antiplatelet agent/a low-dose anticoagulant, in order to achieve the maximum net clinical benefit.
Clinical utility of non-contact charge density ‘SuperMap’ algorithm for the mapping and ablation of organized atrial arrhythmias
Authors: Pope Michael T B , Leo Milena , Briosa e Gala Andre , Betts Timothy R
Published: October 2021

Aims

SuperMap is a novel non-contact algorithm for the mapping of organized atrial arrhythmias. We prospectively evaluated SuperMap during mapping and ablation of atrial tachycardias (ATs) and paced rhythms and compared to conventional high-density contact mapping.

Methods and results

Consecutive patients undergoing SuperMap guided ablation of pre-existing ATs or AT developed during atrial fibrillation ablation procedures were included together with maps obtained during pacing to assess block in linear lesions. The time taken to obtain diagnostic maps was measured together with the number of electrogram (EGM) points and accuracy compared to the arrhythmia diagnosis confirmed using a combination of map findings, entrainment, and response to ablation. In a subgroup of patients, concurrent contact mapping was performed with contact and SuperMap analysed by separate operators blinded to the other technique. The time taken to generate a diagnostic map, EGM number, and map accuracy was compared. Thirty-one patients (62 maps) were included with contact mapping performed in 19 [39 maps (33 for AT)]. SuperMap acquisition time was 314 s [interquartile range (IQR) 239–436]. The median number of EGM points used per map was 5399 (IQR 3279–8677). SuperMap was faster than contact mapping [394 ± 219 s vs. 611 ± 331 s; difference 217 s, 95% confidence interval (CI) 116–318, P < 0.0005]. The number of EGM points used per map was higher for SuperMap (7351 ± 5054 vs. 3620 ± 3211; difference 3731, 95% CI 2073–5388, P < 0.0005). SuperMap and contact mapping were accurate in 92% and 85% of maps, respectively, P = 0.4805.

Conclusion

SuperMap non-contact charge density mapping is a rapid and reliable approach to guide the ablation of complex atrial arrhythmias.
Spatially resolved assembly, connectivity and structure of particle-associated and free-living bacterial communities in a high Arctic fjord
Authors: Jain Anand , Balmonte John Paul , Singh Richa , Bhaskar Parli Venkateswaran , Krishnan Kottekkatu Padinchati
Published: October 2021

The assembly processes that underlie the composition and connectivity of free-living (FL) and particle-associated (PA) bacterial communities from surface to deep waters remain little understood. Here, using phylogenetic null modeling, we quantify the relative influence of selective and stochastic mechanisms that assemble FL and PA bacterial communities throughout the water column in a high Arctic fjord. We demonstrate that assembly processes acting on FL and PA bacterial communities are similar in surface waters, but become increasingly distinct in deep waters. As depth increases, the relative influence of homogeneous selection increases for FL but decreases for PA communities. In addition, dispersal limitation and variable selection increase with depth for PA, but not for FL communities, indicating increased residence time of taxa on particles and less frequent decolonization. As a consequence, beta diversity of PA communities is greater in bottom than in surface waters. The limited connectivity between these communities with increasing depth leads to highly distinct FL and PA bacterial communities in bottom waters. Finally, depth-related trends for FL and PA beta diversity and connectivity in this study are consistent with previous observations in the open ocean, suggesting that assembly processes for FL and PA bacterial communities may also be distinct in other aquatic environments.
Fire impacts bacterial composition in Protea repens (Proteaceae) infructescences
Authors: Human Zander R , Roets Francois , Crous Casparus J , Wingfield Michael J , de Beer Z Wilhelm , Venter Stephanus N
Published: October 2021

The diverse bacterial communities in and around plants provide important benefits, such as protection against pathogens and cycling of essential minerals through decomposition of moribund plant biomass. Biodiverse fynbos landscapes generally have limited deadwood habitats due to the absence of large trees and frequent fire. In this study, we determined the effect of a fire disturbance on the bacterial communities in a fynbos landscape dominated by the shrub Protea repens using 16S ribosomal RNA amplicon sequencing. The bacterial community composition in newly formed fruiting structures (infructescences) and soil at a recently burnt site was different from that in an unburnt site. Bacteria inhabiting P. repens infructescences were similar to well-known taxa from decomposing wood and litter. This suggests a putative role for these aboveground plant structures as reservoirs for postfire decomposer bacteria. The results imply that inordinately frequent fires, which are commonplace in the Anthropocene, are a significant disturbance to bacterial communities and could affect the diversity of potentially important microbes from these landscapes.
Building capacity of community health centers to overcome data challenges with the development of an agile COVID-19 public health registry: a multistate quality improvement effort
Authors: Romero Lisa , Carneiro Pedro B , Riley Catharine , Clark Hollie , Uy Raymonde , Park Michael , Mawokomatanda Tebitha , Bombard Jennifer M , Hinckley Alison , Skapik Julia
Published: October 2021

Objective

During the coronavirus disease 2019 (COVID-19) pandemic, federally qualified health centers rapidly mobilized to provide SARS-CoV-2 testing, COVID-19 care, and vaccination to populations at increased risk for COVID-19 morbidity and mortality. We describe the development of a reusable public health data analytics system for reuse of clinical data to evaluate the health burden, disparities, and impact of COVID-19 on populations served by health centers.

Materials and Methods

The Multistate Data Strategy engaged project partners to assess public health readiness and COVID-19 data challenges. An infrastructure for data capture and sharing procedures between health centers and public health agencies was developed to support existing capabilities and data capacities to respond to the pandemic.

Results

Between August 2020 and March 2021, project partners evaluated their data capture and sharing capabilities and reported challenges and preliminary data. Major interoperability challenges included poorly aligned federal, state, and local reporting requirements, lack of unique patient identifiers, lack of access to pharmacy, claims and laboratory data, missing data, and proprietary data standards and extraction methods.

Discussion

Efforts to access and align project partners’ existing health systems data infrastructure in the context of the pandemic highlighted complex interoperability challenges. These challenges remain significant barriers to real-time data analytics and efforts to improve health outcomes and mitigate inequities through data-driven responses.

Conclusion

The reusable public health data analytics system created in the Multistate Data Strategy can be adapted and scaled for other health center networks to facilitate data aggregation and dashboards for public health, organizational planning, and quality improvement and can inform local, state, and national COVID-19 response efforts.