bluuebunny/crossref_metadata_2025 huggingface dataset:
Sperm DNA Fragmentation
Authors: Karavolos Stamatios
Published: October 2021

Sperm DNA fragmentation refers to the accumulation of adducts as well as single- or double-strand DNA breaks and reflects the sperm DNA quality. Current data suggest that there are differences in sperm DNA quality among individuals with high or low fertility, and this observation has led to the idea that testing sperm DNA fragmentation could be a useful test of male fertility. However, sperm DNA fragmentation has become one of the most frequently debated topics in reproductive medicine, as there is no agreement about the optimal way to test for DNA fragmentation, the clinically significant level of sperm DNA fragmentation, as well as the best therapeutic options for infertile men. This article presents current evidence related to sperm DNA fragmentation and its role in managing male infertility.
Influence of Triple-Negative versus Luminal A Breast Cancer Subtype on Choice of Autologous versus Implant-Based Delayed-Immediate Breast Reconstruction
Authors: Dickey Ryan M. , Amaya Joshua , Teotia Sumeet S. , Haddock Nicholas T.
Published: October 2021

Background Triple-negative (TN) and luminal A breast cancer molecular subtypes have divergent clinical and prognostic characteristics for breast cancer patients. Our study aims to compare the reconstructive choice of these two groups from the time they receive a tissue expander (TE) to the time they complete autologous or implant-based breast reconstruction.

Methods A total of 255 patients who underwent delayed-immediate breast reconstruction with TE placement from 2013 to 2017 diagnosed with either TN (n = 73) or luminal A (n = 182) invasive breast cancer subtype seen by two surgeons at a single institution were identified. Preference of autologous and implant-based reconstruction was analyzed, along with TE complications, race, age, body mass index (BMI), smoking, adjuvant therapy, and comorbidities.

Results There was a significant difference in the choice of implant- or autologous-based reconstruction among these two groups (p < 0.05). A greater proportion of luminal A patients underwent implant-based reconstruction (63.47%) and a greater proportion of TN patients underwent autologous-based reconstruction (53.13%). With regard to TE outcomes, there was no significant difference between the two groups with regard to duration of TE placement by reconstructive type or TE surgical complications. Significantly, more TN patients underwent radiation therapy (p < 0.01) and neoadjuvant chemotherapy (p < 0.0001) than luminal A patients. BMI, comorbidities, radiation therapy, and overall TE complications were identified as predictive factors of patients electing for autologous reconstruction over implants.

Conclusion TN breast cancer patients mostly chose autologous-based reconstruction, while luminal A patients chose implant-based reconstruction. Both patient groups carried their TEs for similar duration with similar complication profile. Radiation therapy is likely a major factor in the decision for the type of delayed-immediate reconstruction among this population.
Preterm Newborn Adaptive Responses to Daily Nursing during Neonatal Intensive Care Unit Stay, Associate with Neurodevelopment, 2 Years Later
Authors: Bembich Stefano , Risso Francesco M. , Stan Nicoleta , Lamba Domitilla , Banova Carolina , Pagnini Arianna , Bin Maura , Trappan Antonella , Sanson Gianfranco
Published: October 2021

Objective This study aimed to evaluate if adaptive responses of very preterm newborns to neonatal intensive care unit (NICU) daily nursing, specifically bathing and weighing procedures are associated with their neurodevelopment after 2 years.

Study Design Twenty-six very preterm newborns, with a gestational age <32 weeks, were enrolled. Infants' adaptive responses to daily nursing were evaluated, at 30 to 32 to 35 postmenstrual age (PMA) weeks by an observational sheet. Neurodevelopment was assessed at 24 months of corrected age by the Bayley Scales of Infant and Toddler Development, third edition. Autonomic, motor, and self-regulatory responses to NICU nursing were analyzed by Spearman's correlation coefficient and multivariate linear regression with Bayley's cognitive, language, and motor scales.

Results Significant (p < 0.05) positive correlations of self-regulatory and autonomic responses to nursing with all Bayley's scales were found at 30- and 32-week PMA. At 35-week PMA, only self-regulatory responses had significant positive correlations with all Bayley's scales. When adjusted for birth weight and sex, the significant associations were confirmed only at 30- and 32-week PMA.

Conclusion Very preterm newborn adaptive responses to NICU daily nursing reveal to be positively related to forthcoming neurodevelopment 2 years later, as early as the 30-week PMA. Helping preterm babies to adapt to daily NICU nursing may promote their future neurobehavior.

Key Points
Social distancing slows down steady dynamics in pedestrian flows
Authors: Kramer Kelby B. , Wang Gerald J.
Published: October 2021

Amidst the ongoing pandemic, social distancing has been broadly adopted as an effective front-line defense strategy for mitigating disease transmission. Viewed through the lens of particle-based simulations of flow, the practice of social distancing corresponds to a (significant) increase in an internal length scale of the flow, namely, the radius within which particles (pedestrians) strongly repel fellow particles. In this study, we report the results of two-dimensional pedestrian dynamics simulations modeling pedestrian counter-flows under confinement, in which individual pedestrians are described as active particles that aim to maintain a target speed while avoiding collisions. By systematically varying two quantities—the pedestrian density and the degree of social distancing—we compute fundamental diagrams for confined and socially distanced pedestrian flows, which show average pedestrian speed as a function of density and social distancing. These results reveal the sensitive dependence of average velocity on both independent variables, including a social distancing-induced jamming transition. These results highlight the need for both deliberate planning and careful public-health messaging regarding social distancing as shared indoor spaces return to appreciable levels of occupation.
A perspective on surface-adsorbed single atom magnets as atomic-scale magnetic memory
Authors: Donati F. , Heinrich A. J.
Published: October 2021

Downscaling single magnetic bits to the ultimate size of individual atoms would open the possibility to maximize the magnetic storage density on a solid surface. However, realizing stable magnets of the size of one atom remained an elusive challenge for more than a decade. Recent advances show that single lanthanide atoms on suitable surfaces can preserve their magnetization on a timescale of days at a temperature of 1 K or below. Such properties enable the use of these atoms as stable magnets for low temperature experiments, opening a platform for testing magnetic recording techniques at the atomic scale. In this article, we describe the single atom magnets that have been investigated and the methods employed to address their magnetic properties. We will discuss the limitations of the present systems and techniques and identify the challenges to close the gap toward potential future technological applications.
A staging table of embryonic development for a viviparous (live-bearing) lizard
Authors: Lin Zhaocun , Yu Kaiming , Shen Leyao , Zhang Yu , Liu Yutian , Hou Mei , Peng Zhennan , Tang Xiaolong , Chen Qiang
Published: October 2021

As the only viviparous reptile in China that has both temperature-dependent sex determination (TSD) and genetic-dependent sex determination (GSD) mechanisms, Eremias multiocellata is considered as an ideal species for studying the sex determination mechanism in viviparous lizards. However, studies on embryonic stage of viviparous lizards and morphological characteristics of each stage are limited. In the present study, the embryonic development process of E. multiocellata is divided into 15 stages (stages 28–42) according to the morphology of embryos. Embryos sizes are measured and continuous dynamic variation of some key features, including limbs, genitals, eyes, pigments, and brain scales are color imaged by a stereoscopic microscope. Furthermore, based on these morphological characteristics, we compare the similarities and differences in the embryonic development of E. multiocellata with other squamate species. Our results not only identified the staging table of E. multiocellata with continuous changes of external morphological characteristics but also developed a staging scheme for an important model species that provides a necessary foundation for study of sex determination in a viviparous lizard.
Miniaturized wireless, skin-integrated sensor networks for quantifying full-body movement behaviors and vital signs in infants
Authors: Jeong Hyoyoung , Kwak Sung Soo , Sohn Seokwoo , Lee Jong Yoon , Lee Young Joong , O’Brien Megan K. , Park Yoonseok , Avila Raudel , Kim Jin-Tae , Yoo Jae-Young , Irie Masahiro , Jang Hokyung , Ouyang Wei , Shawen Nicholas , Kang Youn J. , Kim Seung Sik , Tzavelis Andreas , Lee KunHyuck , Andersen Rachel A. , Huang Yonggang , Jayaraman Arun , Davis Matthew M. , Shanley Thomas , Wakschlag Lauren S. , Krogh-Jespersen Sheila , Xu Shuai , Ryan Shirley W. , Lieber Richard L. , Rogers John A.
Published: October 2021

Significance

Early detection of infant neuromotor pathologies is critical for timely therapeutic interventions that rely on early-life neuroplasticity. Traditional assessments rely on subjective expert evaluations or specialized medical facilities, making them challenging to scale in remote and/or resource-constrained settings. The results presented here aim to democratize these evaluations using wireless networks of miniaturized, skin-integrated sensors that digitize movement behaviors and vital signs of infants in a cost-effective manner. The resulting data yield full-body motion reconstructions in the form of deidentified infant avatars, along with a range of important cardiopulmonary information. This technology approach enables rapid, routine evaluations of infants at any age via an engineering platform that has potential for use in nearly any setting across developed and developing countries alike.
COVID-19 lockdowns drive decline in active fires in southeastern United States
Authors: Poulter Benjamin , Freeborn Patrick H. , Jolly W. Matt , Varner J. Morgan
Published: October 2021

Significance

The coronavirus pandemic, COVID-19, led to strict social-distancing guidelines that severely impacted human livelihood and economic activity. Workplace closures reduced travel, and early in spring 2020, improvements in air and water quality, reduced seismic activity, and reductions in greenhouse gas emissions were observed. COVID-19–related shutdowns emerged at the beginning of the prescribed fire season in the southeastern United States, where 80% of fires are human caused. Using active fire satellite observations and fuel treatment statistics, we estimated a 21% reduction in active fires from March to December 2020 (up to 40% on federal lands). This reduction in active fire may increase fire risk in the future and is detrimental to biodiversity and other ecosystem services inherent to fire-dependent ecosystems.
A new regime of heme-dependent aromatic oxygenase superfamily
Authors: Shin Inchul , Wang Yifan , Liu Aimin
Published: October 2021

Two histidine-ligated heme-dependent monooxygenase proteins, TyrH and SfmD, have recently been found to resemble enzymes from the dioxygenase superfamily currently named after tryptophan 2,3-dioxygenase (TDO), that is, the TDO superfamily. These latest findings prompted us to revisit the structure and function of the superfamily. The enzymes in this superfamily share a similar core architecture and a histidine-ligated heme. Their primary functions are to promote O-atom transfer to an aromatic metabolite. TDO and indoleamine 2,3-dioxygenase (IDO), the founding members, promote dioxygenation through a two-step monooxygenation pathway. However, the new members of the superfamily, including PrnB, SfmD, TyrH, and MarE, expand its boundaries and mediate monooxygenation on a broader set of aromatic substrates. We found that the enlarged superfamily contains eight clades of proteins. Overall, this protein group is a more sizeable, structure-based, histidine-ligated heme-dependent, and functionally diverse superfamily for aromatics oxidation. The concept of TDO superfamily or heme-dependent dioxygenase superfamily is no longer appropriate for defining this growing superfamily. Hence, there is a pressing need to redefine it as a heme-dependent aromatic oxygenase (HDAO) superfamily. The revised concept puts HDAO in the context of thiol-ligated heme-based enzymes alongside cytochrome P450 and peroxygenase. It will update what we understand about the choice of heme axial ligand. Hemoproteins may not be as stringent about the type of axial ligand for oxygenation, although thiolate-ligated hemes (P450s and peroxygenases) more frequently catalyze oxygenation reactions. Histidine-ligated hemes found in HDAO enzymes can likewise mediate oxygenation when confronted with a proper substrate.
On the mechanisms of the influence of preliminary ionization on the plasma dynamics of nanosecond capillary discharges and the properties of discharge-based EUV lasers
Authors: Eliseev S , Samokhvalov A , Zhao Y P , Burtsev V
Published: October 2021

In this paper, we present the results of numerical investigations into the influence of preionization on the properties of extreme ultraviolet (EUV) lasers based on nanosecond capillary discharges. Prior to application of the main current pulse, gas inside the capillary is usually preionized by a separate current pulse with longer duration and lower amplitude, which creates plasma with minimal density on the capillary axis and maximal at the capillary wall. Magnetohydrodynamic simulations were performed for a range of prepulse parameters that defined different degrees of inhomogeneity of this initial profile. It was found that the plasma density distribution at the start of the main current pulse affects the cylindrical shock wave that takes place during the compression stage of a capillary discharge: A lower degree of radial inhomogeneity results in a steeper front of the shock wave. It is further shown that a steeper wave front results in a more concave electron density profile moments before the shock wave collapses on the capillary axis, when the EUV laser pulse presumably takes place, which may lead to a decrease in the rate of refraction losses. The proposed interpretation of the obtained numerical results correlates well with the available experimental data on the dependence of EUV laser pulse intensity and duration on the preliminary pulse amplitude.
The validity of triple contact line theory from hydrophilic to superhydrophobic surfaces
Authors: Taher Md Abu , Rajput Vinod K , Krishnan P K Navanith , Naraharisetty Sri Ram G
Published: October 2021

The anisotropic droplet formulation is generalized from hydrophilic to superhydrophobic surfaces. An experimental method to calibrate the ellipsoidal droplet volume on both hydrophilic and hydrophobic surfaces is presented. A broad range of contact angles (CAs) is produced on the copper and stainless-steel surfaces using femtosecond laser patterning. The effects of line spacing between the laser scanning on the formation of anisotropic CAs are discussed. The comparative study of the evolution of anisotropic CAs and droplet’s spreading dynamics are studied on both surfaces. According to the triple contact line (TCL) theory, CAs are determined by the TCL between droplet and surface rather than the contact area. We presented the mathematical formalism and the experimental validity of the TCL theory on ellipsoidal droplets over a broad range of CAs, from as low as 37°–172°. This work experimentally validated the TCL theory over a broad range of CAs with good confidence.
Critical study of partial discharge inception in voids: statistical behavior to stochastic nature
Authors: Zhang Rui , Zhang Qiaogen , Zhou Junjie , Guo Chong , He Xiaohui , Wu Zhicheng , Wen Tao
Published: October 2021

Although many studies have been done and advanced progress has been made in understanding partial discharge (PD) behavior in the void, this is not the case firinception of PD, especially its stochastic nature. The statistical behaviors of PD inception voltage (PDIV) and inception time delay (PDTD) inside the void were investigated in this study through repeated tests to observe the stochastic nature of PD inception. The results show that the PDIV and PDTD of the void are highly dispersed and obey Weibull and exponential distributions, respectively. The significant dispersion of PDIV can be attributed to the statistical time delay of PD inception. The lengthy inception delay is attributable to a lack of free electrons. The exponential distribution of PDTD indicates that free-electron generation is completely random; further, the stochastic nature of void PD inception is determined by the supply of free electrons. The test method (voltage rise rate, test time, and test time interval), void parameters (size, material, and surface condition), and background radiation determine PD inception by affecting the volume ionization or surface-emission process providing free electrons. Enhanced background ionization or significant increase in test voltage and test time allow for the effective detection of void defects during PD tests. This work contributes to an empirical understanding of the physical process of PD inception in voids and improving existing PD testing technologies.
Critical curves in NiFe/FeMn bilayers with varying antiferromagnetic layer thickness
Authors: Adams D J , Cimpoesu D , Benit S , Maurin D , Kern P R , Carara M , Spinu L
Published: October 2021

The effect of antiferromagnetic (AF) layer thickness on exchange bias was studied in a series of NiFe(50 nm)/FeMn(t) bilayers through both irreversible and reversible experiments at room temperature. The exchange bias was evaluated in the sample plane both through measurement of the major hysteresis loops and probing the reversible susceptibility. The critical curve was constructed to map the angular dependence of the magnetization switching and exchange bias, which is found to evolve as a function of AF layer thickness. Ferromagnetic resonance absorption was measured at several frequencies and angles, and angular-dependent absorption curves were plotted. A comparison is made between the recorded exchange bias using the three methods. The measurements reported are supported by simulations under a generalized Stoner–Wohlfarth model, and general limitations of the experiment are discussed.
Emerging properties of carbon based 2D material beyond graphene
Authors: Jana Susmita , Bandyopadhyay Arka , Datta Sujoy , Bhattacharya Debaprem , Jana Debnarayan
Published: October 2021

Graphene turns out to be the pioneering material for setting up boulevard to a new zoo of recently proposed carbon based novel two dimensional (2D) analogues. It is evident that their electronic, optical and other related properties are utterly different from that of graphene because of the distinct intriguing morphology. For instance, the revolutionary emergence of Dirac cones in graphene is particularly hard to find in most of the other 2D materials. As a consequence the crystal symmetries indeed act as a major role for predicting electronic band structure. Since tight binding calculations have become an indispensable tool in electronic band structure calculation, we indicate the implication of such method in graphene’s allotropes beyond hexagonal symmetry. It is to be noted that some of these graphene allotropes successfully overcome the inherent drawback of the zero band gap nature of graphene. As a result, these 2D nanomaterials exhibit great potential in a broad spectrum of applications, viz nanoelectronics, nanooptics, gas sensors, gas storages, catalysis, and other specific applications. The miniaturization of high performance graphene allotrope based gas sensors to microscopic or even nanosized range has also been critically discussed. In addition, various optical properties like the dielectric functions, optical conductivity, electron energy loss spectra reveal that these systems can be used in opto-electronic devices. Nonetheless, the honeycomb lattice of graphene is not superconducting. However, it is proposed that the tetragonal form of graphene can be intruded to form new hybrid 2D materials to achieve novel superconducting device at attainable conditions. These dynamic experimental prospects demand further functionalization of these systems to enhance the efficiency and the field of multifunctionality. This topical review aims to highlight the latest advances in carbon based 2D materials beyond graphene from the basic theoretical as well as future application perspectives.
Two-dimensional conducting states in infinite-layer oxide/perovskite oxide hetero-structures
Authors: Chen Xiaobing , Zhang Jine , Liu Banggui , Hu Fengxia , Shen Baogen , Sun Jirong
Published: October 2021

Heterointerfaces sandwiched by oxides of dissimilar crystal structures will show strong interface reconstruction, leading to distinct interfacial effect arising from unusual physics. Here, we present a theoretical investigation on the interfaces between infinite-layer oxide and perovskite oxide (SrCuO2/SrTiO3 and SrCuO2/KTaO3). Surprisingly, we found well-defined two-dimensional electron gas (2DEG), stemming from atomic reconstruction and polar discontinuity at interface. Moreover, the 2DEG resides in both the TiO2 and CuO2 interfacial layers, unlike LaAlO3/SrTiO3 for which 2DEG exists only in the TiO2 interfacial layer. More than that, no metal-to-insulator transition is observed as the SrCuO2 layer thickness decreases to one unit cell, i.e., the metallicity of the new interface is robust. Further investigations show more unique features of the 2DEG. Due to the absence of apical oxygen at the SrCuO2/SrTiO3 (KTaO3) interface, the conducting states in the interface TiO2 (TaO2) layer follows the

d

x
y

<

d

3

z

2

−

r

2

<

d

x
z
/
y
z

orbital order rather than the d

xy
< d

xz/yz
orbital order of paradigm LaAlO3/SrTiO3 (KTaO3), exhibiting enhanced interfacial conduction. This work suggests the great potential of heterointerfaces composed of non-isostructural oxides for fundamental research.
Concentration dependent debundling and single tube dispersions of pristine multiwalled carbon nanotubes functionalized with double tail phospholipids
Authors: Nigam Poonam
Published: October 2021

Multiwalled carbon nanotubes (MWNTs) exist as aggregates of highly entangled tubes due to large aspect ratios and strong Van der Waals interactions among them in their native states. In order to render them suitable for any application, MWNTs need to be separated and dispersed uniformly in a solvent preferably as individual tubes. In the present work, it is demonstrated that a double tail lipid such as 1, 2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE) is capable of dispersing MWNTs in ethanol. Ultra-stable suspensions were obtained by optimizing two key parameters: DPPE to MWNT weight ratio (ε) and MWNT concentration (c). Stability of the suspensions increased with the increasingεvalue up to an optimum point (ε= 1.8) and then decreased drastically beyond that. CNT dispersions withε= 1.8 were extremely stable (with a Zeta potential of 108.26 ± 2.15 mV) and could be retained in suspended form up to 3 months. Effect of MWNT concentration on disaggregation was very significant and stable suspensions could be formed for MWNT concentrations only below 0.14 mg ml−1. Above this concentration, no stable dispersions could be obtained even withε= 1.8. Compression isotherms of Langmuir monolayers of the DPPE functionalized MWNTs spread at the air water interface were highly repeatable, suggesting that the MWNTs in dispersion were present as separate tubes coated with phospholipids. SEM micrographs of the Langmuir–Blodgett (LB) films, deposited at high surface pressures on silicon wafers, show that MWNTs remain as single nanotubes with no signs of reaggregation. TEM micrographs of MWNT suspensions indicated random adsorption of DPPE on MWNTs. Our work makes it possible to explore potential applications of LB films of MWNTs (stabilized by DPPE) in the development of conducting thin films for sensor applications or as supports to immobilize catalysts for heterogenous reactions.
Hierarchical colloidosomes self-assembled from block copolymer micelles via emulsion interfacial confinement
Authors: Liu Changxu , Wu Ming , Duan Lijie , Yan Nan , Jiang Wei
Published: October 2021

Hierarchical self-assembly of polymeric building blocks into high-level colloidosomes is desirable to not only design novel nanostructures but also fabricate the complex artificial materials across many length scales with multifunctionality. Although great progress has been made in the designing the hierarchical colloidosomes, the fabrication of polymeric colloidosomes self-assembled from block copolymer (BCP) colloidal nanoparticles still remains challenge. Here, we report the fabrication of the hierarchical polymeric colloidosomes with typical hollow internal structures self-assembled from the polystyrene-block-poly (2-vinyl pyridine) (PS-b-P2VP) BCP spherical micelles through the emulsion interfacial confinement, which is constructed through the water-in-1-butanol emulsion system. Moreover, the hierarchical colloidosomes can disassemble into the original uniform spherical micelles under the acid aqueous solution, indicating that the colloidosomes possess good pH stimuli-responsibility. Finally, the stability of the colloidosomes can be greatly improved by cross-linking the P2VP corona of original spherical micelles, offering the effective templates for construction of the multifunctional materials. This finding provides a simple yet effective method for the fabrication of the hierarchical colloidosomes from the BCP building blocks.
Facile decoration of two-dimensional Ti3C2T
x
nanoplates with CuS nanoparticles via a facile in situ synthesis strategy at room temperature for superhigh specific capacitance of supercapacitors
Authors: Shen Yuanyuan , Jiang Haoli , Lu Zhiyong , Li Gaiye , Wang Zhongchang , Zhang Jianfeng
Published: October 2021

Although supercapacitors have attracted more and more attention owing to their fast charging speed and high power density, their wide applications have still been limited by their low energy density. In this study, a new CuS-nanoparticle-decorated Ti3C2T
x
electrode material is fabricated via a facile in situ synthesis strategy at room temperature. CuS nanoparticles, generated from the in situ reaction of Cu (NO3)2·3H2O with Na2S·9H2O, are anchored between the Ti3C2T
x
interlayers through electrostatic interaction. This type of structural construction is found capable of not only reducing the surface oxidation of Ti3C2T
x
, but also preventing the accumulation of CuS nanoparticles by the template effect of Ti3C2T
x
nanoplates. As a result, the CuS/Ti3C2T
x
nanohybrid delivers a maximum specific capacitance of 911 F g−1 at 1 A g−1 and a good cycling stability. A symmetric supercapacitor fabricated using the CuS/Ti3C2T
x
nanohybrid as the electrode material exhibits an energy density of 43.56 W h kg−1 with a power density of 475 W kg−1. Consequently, this work provides a new perspective of microstructural design for the preparation of electrode materials with superhigh specific capacitance through an easy and low-cost in situ-reaction method at room temperature.
A lithium laser-ablation based time-of-flight (LILA-TOF) diagnostic for measuring plasma edge ion temperature and toroidal plasma rotation
Authors: López-Miranda B , Tabarés F L , McCarthy K J , Baciero A , Tafalla D , Medina F , Ochando M A
Published: October 2021

A new method for studying the thermalization and transport of injected impurities at the edge of hot plasma, (considering the last closed magnetic surface, the free path is between 1 and 2 cm approx.) under no perturbative conditions, is presented. In the proposed technique, a Nd:YAG laser is used to ablate Li from the lithiated wall of the stellarator TJ-II. While the laser pulse allows for the analysis of the released species through laser induced breakdown spectroscopy (LIBS), its laser pulse also provides a time reference for the time-of-flight (TOF) measurements of the Li+ ions performed. This is done by positioning light detection systems sensitive to an intense Li II spectral line at different toroidal locations away from such a source. TOF times of tens to hundreds of microseconds are recorded. Then, by de-convolving the shape of the recorded light pulse, the velocity distribution of the lithium-ion during its thermalization with the background plasma can be extracted. From this velocity distribution, the ion temperature of the background ions and the toroidal rotation at the plasma periphery can be deduced. In contrast with conventional Doppler spectroscopy, this technique uses filter-scope detectors rather than high-spectral-resolution spectrometers thus a tradeoff between spectral and time or space resolution is required. Finally, preliminary results of the application of this novel technique are shown to validate this proof of principle.
The dark side of ambition: side-effects of China’s climate policy
Authors: Xu Hongzhang , Tang Aaron , Pittock Jamie
Published: October 2021

China’s latest commitments to the Paris Agreement have attracted great attention. Scholars have questioned the feasibility of China’s pledges to peak emissions before 2030 and achieve carbon neutrality by 2060. To achieve these goals, China has resorted to extreme emissions reduction actions. However, side-effects of China’s climate ambition have been largely overlooked. An intersectional and just transitions perspective is critical to examine limits and trade-offs for broad societal goals. This paper outlines five policy approaches that can help limit adverse side-effects and unlock broader social benefits.
Repair of critical-size porcine craniofacial bone defects using a collagen–polycaprolactone composite biomaterial
Authors: Dewey Marley J , Milner Derek J , Weisgerber Daniel , Flanagan Colleen L , Rubessa Marcello , Lotti Sammi , Polkoff Kathryn M , Crotts Sarah , Hollister Scott J , Wheeler Matthew B , Harley Brendan A C
Published: October 2021

Regenerative medicine approaches for massive craniomaxillofacial (CMF) bone defects face challenges associated with the scale of missing bone, the need for rapid graft-defect integration, and challenges related to inflammation and infection. Mineralized collagen scaffolds have been shown to promote mesenchymal stem cell osteogenesis due to their porous nature and material properties, but are mechanically weak, limiting surgical practicality. Previously, these scaffolds were combined with 3D-printed polycaprolactone (PCL) mesh to form a scaffold-mesh composite to increase strength and promote bone formation in sub-critical sized porcine ramus defects. Here, we compare the performance of mineralized collagen–PCL composites to the PCL mesh in a critical-sized porcine ramus defect model. While there were no differences in overall healing response between groups, our data demonstrated broadly variable metrics of healing regarding new bone infiltration and fibrous tissue formation. Abscesses were present surrounding some implants and PCL polymer was still present after 9–10 months of implantation. Overall, while there was limited successful healing, with 2 of 22 implants showed substantial levels of bone regeneration, and others demonstrating some form of new bone formation, the results suggest targeted improvements to improve repair of large animal models to more accurately represent CMF bone healing. Notably, strategies to increase osteogenesis throughout the implant, modulate the immune system to support repair, and employ shape-fitting tactics to avoid implant micromotion and resultant fibrosis. Improvements to the mineralized collagen scaffolds involve changes in pore size and shape to increase cell migration and osteogenesis and inclusion or delivery of factors to aid vascular ingrowth and bone regeneration.
Viral alpha-synuclein knockdown prevents spreading synucleinopathy
Authors: Menon Sindhu , Kofoed Rikke H , Nabbouh Fadl , Xhima Kristiana , Al-Fahoum Yasmeen , Langman Tammy , Mount Howard T J , Shihabuddin Lamya S , Sardi S Pablo , Fraser Paul E , Watts Joel C , Aubert Isabelle , Tandon Anurag
Published: October 2021

The accumulation of aggregated alpha-synuclein (α-syn) in Parkinson's disease, dementia with Lewy bodies and multiple system atrophy is thought to involve a common prion-like mechanism, whereby misfolded α-syn provides a conformational template for further accumulation of pathological α-syn. We tested whether silencing α-syn gene expression could reduce native non-aggregated α-syn substrate and thereby disrupt the propagation of pathological α-syn initiated by seeding with synucleinopathy-affected mouse brain homogenates. Unilateral intracerebral injections of adeno-associated virus serotype-1 encoding microRNA targeting the α-syn gene reduced the extent and severity of both the α-syn pathology and motor deficits. Importantly, a moderate 50% reduction in α-syn was sufficient to prevent the spread of α-syn pathology to distal brain regions. Our study combines behavioural, immunohistochemical and biochemical data that strongly support α-syn knockdown gene therapy for synucleinopathies.
The deletion of GluK2 alters cholinergic control of neuronal excitability
Authors: Gorlewicz Adam , Barthet Gael , Zucca Stefano , Vincent Peggy , Griguoli Marilena , Grosjean Noëlle , Wilczynski Grzegorz , Mulle Christophe
Published: October 2021

Kainate receptors (KARs) are key regulators of synaptic circuits by acting at pre- and postsynaptic sites through either ionotropic or metabotropic actions. KARs can be activated by kainate, a potent neurotoxin, which induces acute convulsions. Here, we report that the acute convulsive effect of kainate mostly depends on GluK2/GluK5 containing KARs. By contrast, the acute convulsive activity of pilocarpine and pentylenetetrazol is not alleviated in the absence of KARs. Unexpectedly, the genetic inactivation of GluK2 rather confers increased susceptibility to acute pilocarpine-induced seizures. The mechanism involves an enhanced excitability of GluK2−/− CA3 pyramidal cells compared with controls upon pilocarpine application. Finally, we uncover that the absence of GluK2 increases pilocarpine modulation of Kv7/M currents. Taken together, our findings reveal that GluK2-containing KARs can control the excitability of hippocampal circuits through interaction with the neuromodulatory cholinergic system.
Interferon-stimulated gene 15 pathway is a novel mediator of endothelial dysfunction and aneurysms development in angiotensin II infused mice through increased oxidative stress
Authors: González-Amor María , García-Redondo Ana B , Jorge Inmaculada , Zalba Guillermo , Becares Martina , Ruiz-Rodríguez María J , Rodríguez Cristina , Bermeo Hugo , Rodrigues-Díez Raquel , Rios Francisco J , Montezano Augusto C , Martínez-González Jose , Vázquez Jesús , Redondo Juan Miguel , Touyz Rhian M , Guerra Susana , Salaices Mercedes , Briones Ana M
Published: October 2021

Aims

Interferon-stimulated gene 15 (ISG15) encodes a ubiquitin-like protein that induces a reversible post-translational modification (ISGylation) and can also be secreted as a free form. ISG15 plays an essential role as host-defence response to microbial infection; however, its contribution to vascular damage associated with hypertension is unknown.

Methods and results

Bioinformatics identified ISG15 as a mediator of hypertension-associated vascular damage. ISG15 expression positively correlated with systolic and diastolic blood pressure and carotid intima-media thickness in human peripheral blood mononuclear cells. Consistently, Isg15 expression was enhanced in aorta from hypertension models and in angiotensin II (AngII)-treated vascular cells and macrophages. Proteomics revealed differential expression of proteins implicated in cardiovascular function, extracellular matrix and remodelling, and vascular redox state in aorta from AngII-infused ISG15–/– mice. Moreover, ISG15–/– mice were protected against AngII-induced hypertension, vascular stiffness, elastin remodelling, endothelial dysfunction, and expression of inflammatory and oxidative stress markers. Conversely, mice with excessive ISGylation (USP18C61A) show enhanced AngII-induced hypertension, vascular fibrosis, inflammation and reactive oxygen species (ROS) generation along with elastin breaks, aortic dilation, and rupture. Accordingly, human and murine abdominal aortic aneurysms showed augmented ISG15 expression. Mechanistically, ISG15 induces vascular ROS production, while antioxidant treatment prevented ISG15-induced endothelial dysfunction and vascular remodelling.

Conclusion

ISG15 is a novel mediator of vascular damage in hypertension through oxidative stress and inflammation.
Heightened condition dependent expression of structural coloration in the faces, but not wings, of male and female flies
Authors: White Thomas E , Locke Amy , Latty Tanya
Published: October 2021

Structurally colored sexual signals are a conspicuous and widespread class of ornament used in mate choice, though the extent to which they encode information on the quality of their bearers is not fully resolved. Theory predicts that signaling traits under strong sexual selection as honest indicators should evolve to be more developmentally integrated and exaggerated than nonsexual traits, thereby leading to heightened condition dependence. Here, we test this prediction through examination of the sexually dimorphic faces and wings of the cursorial fly Lispe cana. Males and females possess structural UV-white and golden faces, respectively, and males present their faces and wings to females during close-range, ground-based courtship displays, thereby creating the opportunity for mutual inspection. Across a field-collected sample of individuals, we found that the appearance of the faces of both sexes scaled positively with individual condition, though along separate axes. Males in better condition expressed brighter faces as modeled according to conspecific flies, whereas condition scaled with facial saturation in females. We found no such relationships for their wing interference pattern nor abdomens, with the latter included as a nonsexual control. Our results suggest that the structurally colored faces, but not the iridescent wings, of male and female L. cana are reliable guides to individual quality and support the broader potential for structural colors as honest signals. They also highlight the potential for mutual mate choice in this system, while arguing for 1 of several alternate signaling roles for wing interferences patterns among the myriad taxa which bear them.
The impact of left ventricular size on outcomes after centrifugal-flow left ventricular assist device implantation
Authors: Molina Ezequiel , Jain Amiti , Ahmed Sara , Lam Phillip , Rao Sriram , Hockstein Michael , Kadakkal Ajay , Hofmeyer Mark , Rodrigo Maria , Chou JiLing , Najjar Samer , Sheikh Farooq
Published: October 2021

OBJECTIVES

The influence of preoperative left ventricular size in outcomes following centrifugal-flow left ventricular assist device (LVAD) implantation has not been well characterized.

METHODS

A cohort of 313 patients who received a centrifugal-flow LVAD at a single institution was analysed. Using a maximally selected log-rank statistic, we investigated whether a left ventricular end-diastolic dimension (LVEDD) cut-off point was associated with worse outcomes. The cohort was then divided in 2 groups based on the LVEDD cut-off point.

RESULTS

An LVEDD cut-off point of 59 mm was found to predict worse survival. Smaller LVEDD patients (≤59 mm, N = 52) were older and more likely to have a history of coronary artery disease compared those with a larger LVEDD (>59 mm, N = 261). Smaller LVEDD patients had lower survival compared to larger LVEDD patients (71% vs 85% at 1 year and 58% vs 80% at 2 years, P = 0.003). The need for temporary right ventricular mechanical support was significantly higher in the smaller LVEDD cohort (11.5% vs 1.9%, P = 0.002). Pump flows at time of discharge were lower in the smaller LVEDD group (3.8 vs 4.2 l/min, P = 0.005), who also had a higher incidence of late right ventricular failure (23% vs 12%, P = 0.02), higher rates of gastrointestinal bleeding (0.416 vs 0.256 events per patient-year, P = 0.025) and higher readmissions secondary to low flow alarms (0.429 vs 0.240 events per patient-year, P = 0.007). Multivariable analysis demonstrated that smaller LVEDD, older age, high BUN and high bilirubin levels were independent predictors of worse survival.

CONCLUSIONS

In patients receiving a centrifugal-flow LVAD, smaller preoperative LVEDD (≤59 mm) was associated with lower survival and higher incidence of adverse outcomes.
Cryoablation versus anti-arrhythmic therapy for initial treatment of atrial fibrillation: a systematic review and meta-analysis
Authors: Patel M M , Changal K , Patel N , Elzanaty A
Published: October 2021

Introduction

Atrial fibrillation is a common cardiac arrhythmia that affects approximately 2% of the overall population. Guidelines suggest the use of anti-arrhythmic agents as initial therapy in patients with symptomatic atrial fibrillation, however using cryoablation as a first line therapy might have increased efficacy. The safety and efficacy of cryoablation as initial therapy has not yet been established.

Purpose

We performed a systematic review and meta-analysis of randomized controlled trials to investigate the use of cryoballoon catheter ablation compared to anti-arrhythmic therapy as an initial intervention to prevent recurrence of atrial tachyarrhythmias in patients with atrial fibrillation. We also wanted to determine if using this initial ablative approach did not present increased adverse events.

Methods

A comprehensive search of multiple databases was performed to find randomized control trials that directly compared cryoablation therapy versus anti-arrhythmic therapy as initial treatment for patients with atrial fibrillation. A total of three RCTs met the inclusion criteria (724 patients) and were used in the meta-analysis. The primary outcome of our meta-analysis was recurrence of atrial tachyarrhythmias. The secondary outcome evaluated serious adverse events of each therapy.

Results

The results showed a statistically significant reduction of recurrence of atrial tachyarrhythmic events in patients receiving cryoablation compared to anti-arrhythmic therapy [Risk Ratio (RR): 0.60, 95% CI (0.49, 0.72), P<0.ehab724.03521, I2=0%]. There was no significant difference in serious adverse events between patients receiving cryoablation compared to patients receiving anti-arrhythmic therapy. [Risk Ratio (RR): 1.19, 95% CI (0.71, 2.00), P=0.52, I2=0%].

Conclusion

Our meta-analysis showed that cryoablation therapy as an initial therapy is more efficacious than anti-arrhythmic therapy in patients with atrial fibrillation without an increased risk of serious adverse events.

Funding Acknowledgement

Type of funding sources: None.
Evolution in lesion index durability using the new third generation laser balloon catheter for pulmonary vein isolation – does the mechanical innovation mean also clinical innovation?
Authors: Tohoku S , Bordignon S , Chen S , Chun K R J , Schmidt B
Published: October 2021

Background

The new second- and third-generation endoscopic ablation systems (EAS 2 and EAS 3) have been launched in recent years. We aimed to assess the index lesion durability as well as gap localization using the multigenerational novel technologies in patients with recurrent atrial fibrillation (AF).

Methods

Consecutive patients who underwent the second ablation for recurrent AF following the initial pulmonary vein isolation (PVI) with EAS 2 or EAS 3 were investigated. The persistent durability of PVI and gap localization at the second procedure were analyzed using spiral mapping catheter and three-dimensional mapping system.

Results

A total of 34 patients (EAS3: N=13, 50 PVs, EAS2: N=21, 82 PVs) were enrolled. Repeat procedure was performed mean 11.9±9.3 months after the initial procedure. Persistent durable isolation of all four PVs was recorded in 6 (46.2%) patients in EAS3 and 4 (19.1%) patients in EAS2 (P=0.130). Ninety-one out of 132 (68.9%) PVs were persistently isolated with a higher rate in EAS3 (EAS3: 82.0% vs. EAS2: 61.0%, P=0.0113). A total of 45 gaps were recorded in 41 PVs, of which right superior PV (RSPV) was the predominantly common reconnected vein (15 gaps in 14 PVs) irrespective of generation difference (EAS 3: 4 gaps in 3 PVs and EAS 2: 12 gaps in 11 PVs). Anterior-segment of RSPV was the most common gap distribution (EAS 3: 2 gaps and EAS 2: 6 gaps). Logistic multivariate regression analysis revealed high-dose (≥8.5W) only ablation as an independent predictor of durable PVI (adjusted OR: 3.70, 95% CI [1.408 - 10.003], P=0.008)

Conclusion

The multigenerational technical innovation resulted in a higher index lesion durability in EAS3 guided PVI in patients with recurrent AF. The specific gap patterns frequent at RSPV, especially at the anterior-superior segment, and the feasibility of high-dose ablation were confirmed in successor EASs.

Funding Acknowledgement

Type of funding sources: None.
Optimal ablation targets during second catheter ablation in patients with persistent AF
Authors: Mohanty S , Trivedi C , Della Rocca D G , Gianni C , MacDonald B , Mayedo A , Bassiouny M , Gallinghouse G J , Burkhardt J D , Horton R , Al-Ahmad A , Di Biase L , Natale A
Published: October 2021

Introduction

Pulmonary vein isolation (PVI) is the cornerstone of ablative therapy in atrial fibrillation (AF). However, the one-year success rate after single ablation procedure is known to be up to 60%, necessitating repeat procedures in many.

Purpose

We evaluated the impact of different ablation strategies on procedural success at the second ablation in patients with persistent AF (PerAF).

Methods

Consecutive PerAF patients scheduled to undergo their second ablation were screened and only those that have received PVI plus isolation of left atrial posterior wall (PWI) and superior vena cava (SVC) at the first procedure (n=1390), were included in the analysis. At the second ablation, all reconnected structures were ablated. Additionally, based on operators' decision, non-PV triggers were targeted for ablation.

Patients were classified into two groups based on the ablation strategy: group 1: Re-isolation of reconnected PVs, PW, SVC and group 2: additional ablation of non-PV triggers (from inter-atrial septum, coronary sinus (CS), left atrial appendage (LAA) and crista terminalis). Arrhythmia-monitoring was performed quarterly for 1 year and biannually afterwards. Ablation success was assessed off-antiarrhythmic drugs (AAD).

Results

Of the 1390 patients included in the analysis, 698 were in group 1 and 692 were in group 2.

In group 1, reconnected PV, PW and SVC were re-isolated in 98 (14%), 311 (44.5%) and 173 (24.8%) respectively. In 131 (18.7%) patients, in the absence of any reconnection, CS was empirically isolated.

In group 2, PV, PW and SVC were re-isolated in 83 (12%), 270 (39%) and 113 (16.3%) patients respectively. Additionally, non-PV triggers were ablated in 505 (73%) and empirical isolation of LAA and CS in the absence of detectable triggers and PV reconnection was performed in 187 (27%).

At 2 years of follow-up, 425 (61%) and 602 (87%) from group 1 and 2 were arrhythmia-free off-AAD (p<0.001).

Conclusion

Including non-PV triggers as targets for ablation at the repeat procedure was associated with significantly higher success rate in persistent AF.

Funding Acknowledgement

Type of funding sources: None.