bluuebunny/crossref_metadata_2025 huggingface dataset:
Heat‐not‐burn tobacco (IQOS), oral fibroblasts and keratinocytes: cytotoxicity, morphological analysis, apoptosis and cellular cycle. An in vitro study
Authors: Pagano Stefano , Negri Paolo , Coniglio Maddalena , Bruscoli Stefano , Di Michele Alessandro , Marchetti Maria Cristina , Valenti Chiara , Gambelunghe Angela , Fanasca Luca , Billi Monia , Cianetti Stefano , Marinucci Lorella
Published: May 2021

Objectives

The aim of this work is to investigate the biological effects of IQOS smoking on human gingival fibroblasts and human keratinocytes analysing cell viability, morphology, migration, apoptosis and cell cycle.

Background

Electronic cigarettes and tobacco heating systems have been marketed to reduce smoking damages caused by combustion.

Methods

Human gingival fibroblasts and human keratinocytes viability was determined by a colorimetric assay measuring mitochondrial dehydrogenase activity (MTT assay); after an in vitro exposure of 24 h, cell morphology was analysed with scanning electron microscope and cell migration was tested by Scratch assay, a method to mimic the migration of the cells during wound healing in vivo. Apoptosis and cell cycle were analysed with flow cytometry, and the expression of related genes (p53, Bcl2, p16 and p21) was indagated using real‐time polymerase chain reaction.

Results

IQOS extracts increased both cell viability (23%‐41% with fibroblasts and 30%‐79% with keratinocytes) and migration. No morphological alterations were observed. IQOS extracts did not induced an increase in cell death, but rose the number of S‐ and G2/M‐phase cells. IQOS extracts also significantly increased p53 expression by fibroblasts (undiluted and 6.25% dilution, 2‐ and 3.6‐fold higher, respectively) and reduced both Bcl2 (about two‐ and fivefold, respectively) and p21 expressions (about twofold with both extracts), while on keratinocytes both undiluted and 6.25% dilution extracts increased Bcl2 expression (about four‐ and threefold higher, respectively) and reduced p53 expression (about two‐ and fivefold, respectively).

Conclusion

IQOS smoke seemed to induce proliferation as highlighted by a viability assay, and migration and cell cycle analysis. The increased cell proliferation induced by IQOS devices must be carefully investigated for its possible clinical effects on oral cell populations.
Secondary sclerosing cholangitis as cause of persistent jaundice in patients with severe COVID‐19
Authors: Bütikofer Simon , Lenggenhager Daniela , Wendel Garcia Pedro D. , Maggio Ewerton M. , Haberecker Martina , Reiner Cäcilia S. , Brüllmann Gregor , Buehler Philipp K. , Gubler Christoph , Müllhaupt Beat , Jüngst Christoph , Morell Bernhard
Published: May 2021

Background & Aims

Little is known about cholestasis, including its most severe variant secondary sclerosing cholangitis (SSC), in critically ill patients with coronavirus disease 19 (COVID‐19). In this study, we analysed the occurrence of cholestatic liver injury and SSC, including clinical, serological, radiological and histopathological findings.

Methods

We conducted a retrospective single‐centre analysis of all consecutive patients admitted to the intensive care unit (ICU) as a result of severe COVID‐19 at the University Hospital Zurich to describe cholestatic injury in these patients. The findings were compared to a retrospective cohort of patients with severe influenza A.

Results

A total of 34 patients with severe COVID‐19 admitted to the ICU were included. Of these, 14 patients (41%) had no cholestasis (group 0), 11 patients (32%, group 1) developed mild and 9 patients (27%, group 2) severe cholestasis. Patients in group 2 had a more complicated disease course indicated by significantly longer ICU stay (median 51 days, IQR 25‐86.5) than the other groups (group 0: median 9.5 days, IQR 3.8‐18.3, P = .001; and group 1: median 16 days, IQR 8‐30, P < .05 respectively). Four patients in group 2 developed SSC compared to none in the influenza A cohort. The available histopathological findings suggest an ischaemic damage to the perihilar bile ducts.

Conclusions

The development of SSC represents an important complication of critically ill COVID‐19 patients and needs to be considered in the diagnostic work up in prolonged cholestasis. The occurrence of SSC is of interest in the ongoing pandemic since it is associated with considerable morbidity and mortality.
Genotype–Environment mismatch of kelp forests under climate change
Authors: Vranken Sofie , Wernberg Thomas , Scheben Armin , Severn‐Ellis Anita Alice , Batley Jacqueline , Bayer Philipp Emanuel , Edwards David , Wheeler David , Coleman Melinda Ann
Published: May 2021

Climate change is increasingly impacting ecosystems globally. Understanding adaptive genetic diversity and whether it will keep pace with projected climatic change is necessary to assess species’ vulnerability and design efficient mitigation strategies such as assisted adaptation. Kelp forests are the foundations of temperate reefs globally but are declining in many regions due to climate stress. A lack of knowledge of kelp's adaptive genetic diversity hinders assessment of vulnerability under extant and future climates. Using 4245 single nucleotide polymorphisms (SNPs), we characterized patterns of neutral and putative adaptive genetic diversity for the dominant kelp in the southern hemisphere (Ecklonia radiata) from ~1000 km of coastline off Western Australia. Strong population structure and isolation‐by‐distance was underpinned by significant signatures of selection related to temperature and light. Gradient forest analysis of temperature‐linked SNPs under selection revealed a strong association with mean annual temperature range, suggesting adaptation to local thermal environments. Critically, modelling revealed that predicted climate‐mediated temperature changes will probably result in high genomic vulnerability via a mismatch between current and future predicted genotype–environment relationships such that kelp forests off Western Australia will need to significantly adapt to keep pace with projected climate change. Proactive management techniques such as assisted adaptation to boost resilience may be required to secure the future of these kelp forests and the immense ecological and economic values they support.
Fine root production in a chronosequence of mature reforested mangroves
Authors: Arnaud Marie , Morris Paul J. , Baird Andy J. , Dang Huyen , Nguyen Tai Tue
Published: May 2021

Mangroves are among the world’s most carbon‐dense ecosystems, but have suffered extensive deforestation, prompting reforestation projects. The effects of mangrove reforestation on belowground carbon dynamics are poorly understood. In particular, we do not know how fine root production develops following mangrove reforestation, despite fine root production being a major carbon sink and an important control of mangrove soil accretion.

Using minirhizotrons, we investigated fine root production and its depth variation along a chronosequence of mature Vietnamese mangroves.

Our results showed that fine root production decreases strongly with stand age in the uppermost 32 cm of our soil profiles. In younger mangrove stands, fine root production declines with depth, possibly due to a vertical gradient in soil nutrient availability; while root production in the oldest stand is low at all depths and exhibits no clear vertical pattern. A major fraction of fine root production occurs deeper than 30 cm, depths that are commonly omitted from calculations of mangrove carbon budgets.

Younger mangroves may accrue shallow soil organic matter faster than older mangroves. Therefore, root productivity and forest stand age should be accounted for when forecasting mangrove carbon budgets and resistance to sea‐level rise.
Diffuse sclerosing osteomyelitis of the mandible: A case‐report following the treatment over a 12‐year period
Authors: Mayor Serena , Patel Vinod , Sproat Chris
Published: May 2021

Diffuse sclerosing osteomyelitis (DSO) is a rare inflammatory disease of the bone with a poorly understood aetiology. We present a case of a 26‐year‐old female with DSO, who has been living with this condition for over 12 years. Many different therapies have been used to attempt to manage her symptoms. She is currently taking oral alendronic acid when she is symptomatic. This case report demonstrates the complexity of managing cases of DSO, as we focus on the multiple treatment modalities used in this case and the response to these. Many cases in literature discuss the use of intravenous bisphosphonates, however, this is linked with a higher risk of medically related osteonecrosis of the jaw. In addition to other reported case studies and research, this case provides further evidence to support the use of oral bisphosphonates in the management of DSO.
Impact of Tibial Component Coronal Alignment on Knee Joint Biomechanics Following Fixed‐bearing Unicompartmental Knee Arthroplasty: A Finite Element Analysis
Authors: Nie Yong , Yu Qiang , Shen Bin
Published: May 2021

Objective

Unicompartmental knee arthroplasty (UKA) has indicated a higher rate of revision than total knee arthroplasty (TKA). The success of UKA depends on UKA component alignment, fixation, and soft tissue integrity. The purpose of this study was to investigate the effects of different tibial component alignments in the coronal plane on the stress distribution in UKA. It was hypothesized that the stress distribution would approach native knee when the tibial component was neutrally positioned.

Methods

The left legs from two healthy volunteers were considered to represent the geometric native knee models. All bones within the knee joint were extracted from the three‐dimensional (3D) computed tomography (CT). MRI was used to generate cartilage, menisci, and four major ligaments. The UKA components were virtually implanted in the medial compartment of the knee model using MIMICS. A total of five different configurations of UKA tibial obliquity in the coronal plane (neutral, 3° varus, 6° varus, 3° valgus, and 6° valgus) were adopted and investigated. Subject‐specific inhomogeneous material properties of bones were used in the finite element analysis (FEA) model. The von Mises stress in the tibia platform and proximal tibia, and the load distribution between the medial and lateral compartments were extracted and compared among the five different configurations.

Results

The inhomogeneous material properties of the trabecular bone were closer to real physics than traditional homogeneous methods. Neutral and 3° varus alignments of the tibial component in the coronal plane have better stress distribution between medial and lateral compartment as healthy knee models, and less stress‐shielding effects than other UKA configurations. The stress pathway under the medial tibia platform in neutral and 3° varus UKA configurations was similar and more obvious than the other three UKA configurations. Notably, the stress of the medial tibia platform in the 3° varus UKA models was more homogenous than the neutral UKA configuration. The 6° varus, 3° valgus, and 6° valgus UKA models had higher stress at the location of anterolateral and posterolateral tibia platform than other UKA configurations.

Conclusion

Neutral or 3° varus positioned in the coronal plane for the tibial component could be the optimal alignment for UKA. Excessive varus or valgus obliquity in the coronal plane lead to significant differences in bone stress transfer and load distribution in the knee, and increase the risk of UKA failure.
E‐learning cultural competence for public health workers: A feasibility and pilot study
Authors: Chae Duckhee , Kim Yunekyong , Ryu Jeeheon , Asami Keiko , Kim Jaseon , Kim Kukhyeon
Published: May 2021

Objective

To describe the development, feasibility, and preliminary efficacy of a seven‐module e‐learning for enhancing cultural competence of public health workers.

Design

The study was based on the framework of the new Medical Research Council; a mixed methods design was used.

Sample

A four‐week pilot cluster‐randomized controlled trial was conducted with 39 public health workers and 74 migrants in South Korea. Feasibility and preliminary efficacy were assessed according to initiation, retention, adherence, usability, acceptability, individual and organizational cultural competence, and migrant trust and satisfaction. Quantitative data were collected at baseline, 4 weeks, and 12 weeks. Focus group interviews were conducted with eight public health workers at 12 weeks.

Results

Initiation, retention, and adherence rates were high. Participants agreed on acceptability, but exhibited mixed results on usability. Participants were satisfied with “well‐structured content,” “authentic case stories and videos,” “increased interest in migrant care,” and “opportunity for self‐reflection.” However, “flawless and trouble‐free system,” “screen design for easy navigation,” “instructor's expertise,” and “more situational cases and videos” were desired. Statistically significant differences were observed for individual cultural competence, migrant trust, and satisfaction.

Conclusion

Generally, the intervention seems feasible and has preliminary efficacy, yet usability improvement is necessary for full‐scale randomized controlled trials.
Contemporary Concise Review 2020: Sleep
Authors: Ainge‐Allen Henry W. , Yee Brendon J. , Ip Mary S. M.
Published: May 2021

SUMMARY OF KEY POINTS

Obstructive sleep apnoea (OSA) now affects one‐seventh of the world's population.

Treatment of even mild OSA can improve daytime sleepiness and quality of life.

Recent modifications to uvulopalatopharyngoplasty may make it a more widely applicable treatment option in selected patients with OSA.

Diet and exercise have effects on sleep apnoea severity independent of weight loss.

Insomnia has become increasingly common during the coronavirus disease 2019 (COVID‐19) pandemic.
Spillover of zoonotic pathogens: A review of reviews
Authors: Sánchez Cecilia A. , Venkatachalam‐Vaz Joy , Drake John M.
Published: May 2021

Zoonotic spillover and subsequent disease emergence cause significant, long‐lasting impacts on our social, economic, environmental and political systems. Identifying and averting spillover transmission is crucial for preventing outbreaks and mitigating infectious disease burdens. Investigating the processes that lead to spillover fundamentally involves interactions between animals, humans, pathogens and the environments they inhabit. Accordingly, it is recognized that transdisciplinary approaches provide a more holistic understanding of spillover phenomena. To characterize the discourse about spillover within and between disciplines, we conducted a review of review papers about spillover from multiple disciplines. We systematically searched and screened literature from several databases to identify a corpus of review papers from ten academic disciplines. We performed qualitative content analysis on text where authors described either a spillover pathway, or a conceptual gap in spillover theory. Cluster analysis of pathway data identified nine major spillover processes discussed in the review literature. We summarized the main features of each process, how different disciplines contributed to them, and identified specialist and generalist disciplines based on the breadth of processes they studied. Network analyses showed strong similarities between concepts reviewed by ‘One Health’ disciplines (e.g. Veterinary Science & Animal Health, Public Health & Medicine, Ecology & Evolution, Environmental Science), which had broad conceptual scope and were well‐connected to other disciplines. By contrast, awas focused on processes that are relatively overlooked by other disciplines, especially those involving food behaviour and livestock husbandry practices. Virology and Cellular & Molecular Biology were narrower in scope, primarily focusing on concepts related to adaption and evolution of zoonotic viruses. Finally, we identified priority areas for future research into zoonotic spillover by studying the gap data.
Real-Time State of Charge Estimation of the Extended Kalman Filter and Unscented Kalman Filter Algorithms Under Different Working Conditions
Authors: Peng Xiongbin , Li Yuwu , Yang Wei , Garg Akhil
Published: May 2021

In the battery management system (BMS), the state of charge (SOC) is a very influential factor, which can prevent overcharge and over-discharge of the lithium-ion battery (LIB). This paper proposed a battery modeling and online battery parameter identification method based on the Thevenin equivalent circuit model (ECM) and recursive least squares (RLS) algorithm with forgetting factor. The proposed model proved to have high accuracy. The error between the ECM terminal voltage value and the actual value basically fluctuates between ±0.1 V. The extended Kalman filter (EKF) algorithm and the unscented Kalman filter (UKF) algorithm were applied to estimate the SOC of the battery based on the proposed model. The SOC experimental results obtained under dynamic stress test (DST), federal urban driving schedule (FUDS), and US06 cycle conditions were analyzed. The maximum deviation of the SOC based on EKF was 1.4112–2.5988%, and the maximum deviation of the SOC based on UKF was 0.3172–0.3388%. The SOC estimation method based on UKF and RLS provides a smaller deviation and better adaptability in different working conditions, which makes it more implementable in a real-world automobile application.
Effect of Viscosity Transition on Oil Flow in Shale and Tight Rocks
Authors: Cui Jiangfeng
Published: May 2021

It has been frequently hypothesized that there is an “effective immobile layer” attached at the solid–liquid interface to represent the hindering effect because of the complicated composition on the flow of crude oil in nanopores. Nevertheless, the resulting viscosity discontinuity is physically problematic, and the effect of viscosity transition was not incorporated. In this paper, based on the reduced form of the continuous viscosity profile, the numerical and analytical models for reduced velocity profiles (quantifying the magnitude and the shape) and the reduced pore radius (the ratio of equivalent and actual pore radii) are obtained and compared with each other, respectively. The reduced pore radius establishes a link between the “effective immobile-layer” simplification and the viscosity transition. Detailed sensitivity analysis is conducted to study the impact of viscosity transition (indicated by the curvature constant and the viscosity ratio) on the reduced viscosity profile, reduced velocity profiles, and the reduced pore radius, separately. Results show the microscale flow patterns that cannot be reflected by the existing body of methodology. This work is important for understanding the flow characteristics of crude oil in shale and tight rocks, where nanopores are dominating and the effect of the interfacial viscosity transition can be significant.
Interception and rendezvous: An intuition-building approach to orbital dynamics
Authors: Edlund Eric M.
Published: May 2021

The problem of rendezvous, the meeting of spacecraft in orbit, is an important aspect of mission planning. We imagine a situation where a chaser craft, initially traveling on the same circular orbit as its target and separated from it by a known distance, must select an initial thrust vector that will allow it to meet the target (interception) followed by a second thrust vector that will allow it to match velocities with the target (rendezvous). The analysis presented here provides solutions to this problem in simple algebraic forms while offering many rich challenges that support intuition-building exercises for students across a range of skill levels. An html-javascript orbit calculator is made available with this manuscript as a supporting visual aid and can be used to test the analysis and explore the consequences of different orbital intercept solutions.
Searching a quantum database with Grover's search algorithm
Authors: Kain Ben
Published: May 2021

The development of programming languages for quantum computing has increased rapidly over the last few years, making it practical for a hands-on approach in teaching quantum computation. In this paper, I introduce the standard textbook example of searching for one item out of four using Grover's search algorithm and extend it by including a quantum database. In addition to explaining how to include a quantum database using a quantum circuit model, I give a complete program implementing the algorithm written in the quantum computing language Qiskit from IBM. If presented in the classroom, this extension of Grover's search algorithm alleviates some unsatisfying aspects of the standard textbook example. If given as an exercise to students, it allows them to extend the standard example and provides experience in developing quantum algorithms. I also outline searching for one (or more) items out of eight with a quantum database, which could be used for student projects.
Naïve Bohr-type quantization for power-law potentials
Authors: Katriel Jacob
Published: May 2021

The naïve Bohr quantization condition mvr=nℏ is applied to arbitrary spherically symmetric power-law potentials. The dependence of the energy eigenvalues on the principal quantum number n agrees with fully quantum mechanical results either exactly (for the hydrogen atom, the harmonic oscillator, and the infinite square well) or asymptotically (the linear potential). This naïve treatment can be used in precalculus, high-school, or “quantum theory for poets” expositions.
Environmental and Psychophysical Heat Stress in Adolescent Tennis Athletes
Authors: Misailidi Maria , Mantzios Konstantinos , Papakonstantinou Christos , Ioannou Leonidas G. , Flouris Andreas D.
Published: May 2021

Purpose: We investigated the environmental conditions in which all outdoor International Tennis Federation (ITF) junior tournaments (athlete ages: <18 y) were held during 2010–2019. Thereafter, we performed a crossover trial (ClinicalTrials.gov: NCT04197375) assessing the efficacy of head–neck precooling for mitigating the heat-induced psychophysical and performance impacts on junior athletes during tennis match play. Methods: ITF junior tournament information was collected. We identified meteorological data from nearby (13.6 [20.3] km) weather stations for 3056 (76%) tournaments. Results: Overall, 30.1% of tournaments were held in hot (25°C–30°C wet-bulb globe temperature [WBGT]; 25.9%), very hot (30°C–35°C WBGT; 4.1%), or extremely hot (>35°C WBGT; 0.1%) conditions. Thereafter, 8 acclimatized male junior tennis athletes (age = 16.0 [0.9] y; height = 1.82 [0.04] m; weight = 71.3 [11.1] kg) were evaluated during 2 matches: one with head–neck precooling (27.7°C [2.2°C] WBGT) and one without (27.9°C [1.8°C] WBGT). Head–neck precooling reduced athletes’ core temperature from 36.9°C (0.2°C) to 36.4°C (0.2°C) (P = .001; d = 2.4), an effect reduced by warm-up. Head–neck precooling reduced skin temperature (by 0.3°C [1.3°C]) for the majority of the match and led to improved (P < .05) perceived exertion (by 13%), thermal comfort (by 14%), and thermal sensation (by 15%). Muscle temperature, heart rate, body weight, and urine specific gravity remained unaffected (P ≥ .05; d < 0.2). Small or moderate improvements were observed in most performance parameters assessed (d = 0.20–0.79). Conclusions: Thirty percent of the last decade’s ITF junior tournaments were held in hot, very hot, or extremely hot conditions (25°C–36°C WBGT). In such conditions, head–neck precooling may somewhat lessen the physiological and perceptual heat strain and lead to small to moderate improvements in the match-play performance of adolescent athletes.
The Effect of Resistance Exercise Priming in the Morning on Afternoon Sprint Cross-Country Skiing Performance
Authors: Rud Bjarne , Øygard Eivind , Dahl Even B. , Paulsen Gøran , Losnegard Thomas
Published: May 2021

Purpose: We tested whether a single session of heavy-load resistance priming conducted in the morning improved double-poling (DP) performance in the afternoon. Methods: Eight national-level male cross-country skiers (mean [SD]: 23 [3] y, 184 [6] cm, 73 [7] kg, maximum oxygen consumption = 69 [6] mL·kg−1·min−1) carried out 2 days of afternoon performance tests. In the morning, 5 hours before tests, subjects were counterbalanced to either a session of 3 × 3 repetitions (approximately 85%–90% 1-repetition maximum) of squat and sitting pullover exercises or no exercise. The performance was evaluated in DP as time to exhaustion (TTE) (approximately 3 min) on a treadmill and 30-m indoor sprints before and after TTE (30-m DP pre/post). Furthermore, submaximal DP oxygen cost, countermovement jump, and isometric knee-extension force during electrical stimulation were conducted. Participants reported perceived readiness on test days. Results: Resistance exercise session versus no exercise did not differ for TTE (approximately 3 min above) (mean ± 95% confidence interval = 3.6% ± 6.0%; P = .29; effect size [ES], Cohen d = 0.27), 30-m DP pre (−0.56% ± 0.80%; P = .21; ES = 0.20), 30-m DP post (−0.18% ± 1.13%; P = .76; ES = 0.03), countermovement jump (−2.0% ± 2.8%; P = .21; ES = 0.12), DP oxygen cost (−0.13% ± 2.04%; P = .91; ES = 0.02), or perceived readiness (P ≥ .11). Electrical stimulation force was not different in contraction or relaxation time but revealed low-frequency fatigue in the afternoon for the resistance exercise session only (−12% [7%]; P = .01; ES = 1.3). Conclusion: A single session of heavy-load, low-volume resistance exercise in the morning did not increase afternoon DP performance of short duration in high-level skiers. However, leg low-frequency fatigue after resistance priming, together with the presence of small positive effects in 2 out of 3 DP tests, may indicate that the preconditioning was too strenuous.
Nonreplicable publications are cited more than replicable ones
Authors: Serra-Garcia Marta , Gneezy Uri
Published: May 2021

Published papers that fail to replicate are cited more than those that replicate, even after the failure is published.
Gas-phase synthesis of benzene via the propargyl radical self-reaction
Authors: Zhao Long , Lu Wenchao , Ahmed Musahid , Zagidullin Marsel V. , Azyazov Valeriy N. , Morozov Alexander N. , Mebel Alexander M. , Kaiser Ralf I.
Published: May 2021

The propargyl self-reaction leading to C
6
H
6
isomers is critical in our understanding of the evolution of carbon in our galaxy.
A highly stable lithium metal anode enabled by Ag nanoparticle–embedded nitrogen-doped carbon macroporous fibers
Authors: Fang Yongjin , Zhang Song Lin , Wu Zhi-Peng , Luan Deyan , Lou Xiong Wen (David)
Published: May 2021

Ag nanoparticle–embedded nitrogen-doped carbon macroporous fibers are rationally designed as the host for Li metal anodes.
Cryo–electron microscopy structure of the antidiuretic hormone arginine-vasopressin V2 receptor signaling complex
Authors: Bous Julien , Orcel Hélène , Floquet Nicolas , Leyrat Cédric , Lai-Kee-Him Joséphine , Gaibelet Gérald , Ancelin Aurélie , Saint-Paul Julie , Trapani Stefano , Louet Maxime , Sounier Rémy , Déméné Hélène , Granier Sébastien , Bron Patrick , Mouillac Bernard
Published: May 2021

Structures of the AVP-V2R-G
s
protein complex provide molecular insights into the function of this clinically relevant target.
Blind spots thwart global coronavirus tracking
Authors: Wadman Meredith
Published: May 2021

With sequencing concentrated in wealthy countries, variants can arise unseen.
A psychedelic win raises questions for PTSD therapy
Authors: Servick Kelly
Published: May 2021

MDMA tested along with talk therapy, but the ideal pairing has yet to be studied.
China overhauls its public health bureaucracy
Authors: Normile Dennis
Published: May 2021

Early stumbles in pandemic response prompt new top-level agency to better handle future threats.
A dead battery dilemma
Authors: Morse Ian
Published: May 2021

With millions of electric vehicles set to hit the road, scientists are seeking better battery recycling methods.
Observation of superfluidity in a strongly correlated two-dimensional Fermi gas
Authors: Sobirey Lennart , Luick Niclas , Bohlen Markus , Biss Hauke , Moritz Henning , Lompe Thomas
Published: May 2021

Finding the breaking point

A superfluid can flow without viscosity but only if the speed of the flow is lower than the so-called critical velocity. Sobirey
et al.
measured the critical velocity of a system of ultracold fermionic atoms confined to two dimensions. The researchers trapped a gas of lithium-6 atoms in a box-shaped potential and then moved another, periodic potential through the trap. The response of the gas to this perturbation showed a sudden increase when the speed of the periodic potential reached the critical velocity.

Science
, abc8793, this issue p.
844
A brain-computer interface that evokes tactile sensations improves robotic arm control
Authors: Flesher Sharlene N. , Downey John E. , Weiss Jeffrey M. , Hughes Christopher L. , Herrera Angelica J. , Tyler-Kabara Elizabeth C. , Boninger Michael L. , Collinger Jennifer L. , Gaunt Robert A.
Published: May 2021

A boost for brain–computer interfaces

The finely controlled movement of our limbs requires two-way neuronal communication between the brain and the body periphery. This includes afferent information from muscles, joints, and skin, as well as visual feedback to plan, initiate, and execute motor output. In tetraplegia, this neural communication is interrupted in both directions at the level of the spinal cord. Brain–computer interfaces have been developed to produce voluntary motor output controlled by directly recording from brain activity. Flesher
et al.
added an afferent channel to the brain–computer interface to mimic sensory input from the skin of a hand (see the Perspective by Faisal). The improvements achieved by adding the afferent input were substantial in a battery of motor tasks tested in a human subject.

Science
, abd0380, this issue p.
831
; see also abi7262, p.
791
The impact of early childhood interventions on mothers
Authors: Evans David K. , Jakiela Pamela , Knauer Heather A.
Published: May 2021

Failure to measure the impacts on women's time and other maternal outcomes implicitly sets their value at zero
Lipid exchanges drove the evolution of mutualism during plant terrestrialization
Authors: Rich Mélanie K. , Vigneron Nicolas , Libourel Cyril , Keller Jean , Xue Li , Hajheidari Mohsen , Radhakrishnan Guru V. , Le Ru Aurélie , Diop Seydina Issa , Potente Giacomo , Conti Elena , Duijsings Danny , Batut Aurélie , Le Faouder Pauline , Kodama Kyoichi , Kyozuka Junko , Sallet Erika , Bécard Guillaume , Rodriguez-Franco Marta , Ott Thomas , Bertrand-Michel Justine , Oldroyd Giles E. D. , Szövényi Péter , Bucher Marcel , Delaux Pierre-Marc
Published: May 2021

Fungal symbiosis with early land plants

Hundreds of millions of years ago, evolved descendants of aquatic plants began showing up on dry land. These newly terrestrialized species had to deal with increased ultraviolet light exposure, desiccation, and less accessible nutrients. Rich
et al.
show how mutualist fungi may have helped these nascent plant lineages with adaptation to their newly challenging environment (see the Perspective by Bouwmeester). Genetic and metabolic analysis of a liverwort as a representative of such plants suggests that the mutually beneficial exchange of nutrients with arbuscular mycorrhizal fungi may have been a feature of these most early land plants.

Science
, abg0929, this issue p.
864
; see also abi8016, p.
789
Biphenylene network: A nonbenzenoid carbon allotrope
Authors: Fan Qitang , Yan Linghao , Tripp Matthias W. , Krejčí Ondřej , Dimosthenous Stavrina , Kachel Stefan R. , Chen Mengyi , Foster Adam S. , Koert Ulrich , Liljeroth Peter , Gottfried J. Michael
Published: May 2021

Biphenylene carbon sheets

Although graphene forms two-dimensional carbon sheets, other arrangements of carbon rings could also assemble as flat sheers. Fan
et al.
synthesized an ultraflat biphenylene carbon sheet consisting of sp
2
-hybridized carbon atoms forming four-, six-, and eight-membered rings on a gold surface. An adsorbed halogenated terphenyl molecule undergoes a two-step interpolymer dehydrofluorination polymerization that creates the four- and eight-membered rings through carbon–carbon bond formation. Scanning tunneling spectroscopy revealed that this carbon allotrope is metallic.

Science
, abg4509, this issue p.
852
Emerging H5N8 avian influenza viruses
Authors: Shi Weifeng , Gao George F.
Published: May 2021

The global spread of H5N8 avian influenza viruses is a public health concern
Tanking up energy through atypical charging
Authors: Hu Bo , Liu T. Leo
Published: May 2021

Designed ketone molecules can undergo two-electron charge storage in aqueous solutions
Putting touch into action
Authors: Faisal A. Aldo
Published: May 2021

Bidirectional brain-machine interfaces boost movement restoration in a paralyzed user
Cutaneous innate immune tolerance is mediated by epigenetic control of MAP2K3 by HDAC8/9
Authors: Sawada Yu , Nakatsuji Teruaki , Dokoshi Tatsuya , Kulkarni Nikhil Nitin , Liggins Marc C. , Sen George , Gallo Richard L.
Published: May 2021

Inhibition of HDAC8 and HDAC9 impairs keratinocyte tolerance of TLR ligand stimulation, leading to cutaneous inflammation.
New Perspectives on Antimicrobial Agents: Cefiderocol
Authors: McCreary Erin K. , Heil Emily L. , Tamma Pranita D.
Published: May 2021

Bacterial resistance to carbapenem agents has reached alarming levels. Accordingly, collaborative efforts between national and international organizations and the pharmaceutical industry have led to an impressive expansion of commercially available β-lactam agents in recent years.
Aminoglycosides Antagonize Bacteriophage Proliferation, Attenuating Phage Suppression of Bacterial Growth, Biofilm Formation, and Antibiotic Resistance
Authors: Zuo Pengxiao , Yu Pingfeng , Alvarez Pedro J. J.
Published: May 2021

The coexistence of residual antibiotics and phages is common in many environments, which underscores the need to understand their interactive effects on bacteria and the implications for antibiotic resistance propagation. Here, aminoglycosides acting as bacterial protein synthesis inhibitors impeded the replication of various phages.
Bacterial Carriage of Genes Encoding Fibronectin-Binding Proteins Is Associated with Long-Term Persistence of Staphylococcus aureus in the Nasal and Gut Microbiota of Infants
Authors: Nowrouzian Forough L. , Ljung Annika , Hesselmar Bill , Nilsson Staffan , Adlerberth Ingegerd , Wold Agnes E.
Published: May 2021

S. aureus
may cause severe infections and frequently colonizes the nose. Nasal carriage of
S. aureus
increases 3-fold the risk of invasive
S. aureus
infection.
S. aureus
is also commonly found in the gut microbiota of infants and young children.
DivIVA Regulates Its Expression and the Orientation of New Septum Growth in Deinococcus radiodurans
Authors: Chaudhary Reema , Kota Swathi , Misra Hari S.
Published: May 2021

In rod-shaped Gram-negative bacteria, the midcell position for binary fission is relatively easy to model. In cocci that do not have predefined poles, the plane of next cell division is shown to be perpendicular to the previous plane.
Supplemental Material: Authigenic berthierine and incipient chloritization in shallowly buried sandstone reservoirs: Key role of the source-to-sink context
Authors: Virolle Maxime , Brigaud Benjamin , al. et
Published: May 2021

Table S1 displaying sample description and petrographical/mineralogical composition (sample list, well location projection WGS84, sample depth, petrographical and clay mineral quantifications).
Synthesis of (E)-5-Arylvinyl-7-methyltetrazolo[1,5-a]pyrimidines
Authors: Gein V. L. , Prudnikova A. N. , Kurbatova A. A. , Dmitriev M. V.
Published: May 2021

A three-component reaction of 5-aminotetrazole with aromatic aldehydes and
acetylacetone under solvent- and catalyst-free conditions at a temperature of
150–160°С proceeds with the formation of (E)-5-arylvinyl-7-methyltetrazolo[1,5-a]pyrimidines. 5,7-Dimethyltetrazolo[1,5-a]pyrimidine is formed as a side-product of the reaction.
Neuronal exosome proteins: novel biomarkers for predicting neonatal response to therapeutic hypothermia
Authors: Pineles Beth , Mani Arunmani , Sura Livia , Rossignol Candace , Albayram Mehmet , Weiss Michael David , Goetzl Laura
Published: May 2021

Objective

Central nervous system (CNS) derived exosomes can be purified from peripheral blood and have been used widely in adult neurological disease. Application to neonatal neurological disease deserves investigation in the setting of hypoxic–ischaemic encephalopathy (HIE).

Design

Observational cohort.

Setting

Level III neonatal intensive care unit.

Participants

Term/near-term neonates undergoing therapeutic hypothermia (TH) for HIE.

Interventions

Blood samples were collected at 0–6, 12, 24, 48 and 96 hours of life.

Main outcomes and measures

CNS exosomes were purified from serum using previously described methods. Biomarker protein levels were quantified using standard ELISA methods and normalised to exosome marker CD-81. The slope of change for biomarker levels was calculated for each time interval. Our primary outcome was MRI basal ganglia/watershed score of ≥3.

Results

26 subjects were included (umbilical artery pH range 6.6–7.29; 35% seizures). An increasing MRI injury score was significantly associated with decreasing levels of synaptopodin between 0–6 and 12 hours (p=0.03) and increasing levels of lipocalin-2 (NGAL) between 12 and 48 hours (p<0.0001). Neuronal pentraxin was not significant. The negative predictive values for increasing synaptopodin and decreasing NGAL was 70.0% and 90.9%, respectively.

Conclusions and relevance

Our results indicate that CNS exosome cargo has the potential to act as biomarkers of the severity of brain injury and response to TH as well as quantify pharmacological response to neuroactive therapeutic/adjuvant agents. Rigorous prospective trials are critical to evaluate potential clinical use of exosome biomarkers.
Late urological manifestation of stress incontinence surgery
Authors: Salfity Louay , Dekel Etay , Sahai Arun , Faure Walker Nicholas
Published: May 2021

The Stamey procedure was a popular procedure for female stress incontinence practiced widely in the 1980s before it was abandoned owing to high complication rates. The procedure aimed to suspend the bladder neck by placing two transvaginal Dacron buttress grafts either side of the bladder neck and suspending them with sutures passed through the retropubic space and tied suprapubically. Erosion of the graft into the bladder was a recognised complication. We report a case of an 84-year-old lady who presented with urinary symptoms forty years after an unspecified stress incontinence procedure. Imaging and cystoscopy revealed an eroded graft in her bladder wall. Further investigation revealed the graft was a Dacron buttress from a Stamey procedure. This case highlights the importance of having a working knowledge of historical techniques that may present with complications many years later and recognising the symptoms that should prompt early investigation.
Mismatched ambition, execution and outcomes: implementing maternal death surveillance and response system in Mtwara region, Tanzania
Authors: Said Ali , Sirili Nathanael , Massawe Siriel , Pembe Andrea B , Hanson Claudia , Malqvist Mats
Published: May 2021

Background

Since 2015, Tanzania has been implementing the Maternal Death Surveillance and Response (MDSR) system. The system employs interactions of health providers and managers to identify, notify and review maternal deaths and recommend strategies for preventing further deaths. We aimed to analyse perceptions and experiences of health providers and managers in implementing the MDSR system.

Methods

An exploratory qualitative study was carried out with 30 purposively selected health providers and 30 health managers in four councils from the Mtwara region between June and July 2020. Key informant interviews and focus group discussions were used to collect data. Inductive thematic analysis was used to analyse data.

Results

Two main themes emerged from this study: ‘Accomplishing by ambitions’ and ‘A flawed system’. The themes suggest that health providers and managers have a strong desire to make the MDSR system work by making deliberate efforts to implement it. They reported working hard to timely notify, review death and implement action plans from meetings. Health providers and managers reported that MDSR has produced changes in care provision such as behavioural changes towards maternal care, increased accountability and policy changes. The system was however flawed by lack of training, organisational problems, poor coordination with other reporting and quality improvements systems, assigning blame and lack of motivation.

Conclusion

The implementation of the MDSR system in Tanzania faces systemic, contextual and individual challenges. However, our results indicate that health providers and managers are willing and committed to improve service delivery to avoid maternal deaths. Empowering health providers and managers by training and addressing the flaws will improve the system and quality of care.
1 The adoption of an empowered physical training programme in a military population – the benefit in injury reduction. A retrospective cohort study
Authors: Downes Graeme , Doddington Luke
Published: May 2021

Introduction

Musculoskeletal injuries (MSKI) represent a significant burden within the British Army, this has been extensively studied amongst recruits. It was decided to study the injury rates of a Light Cavalry Squadron who have adopted an empowered physical training program involving personal responsibility for physical training with periodic benchmark exercises.

Methods

Anonymised data were collected between April and August 2020 during an operational tour. The number of presentations to the medical centre for MSKI as well as the number of days of restricted duties were collected. The data relating to the same operational tour, exactly one year previously, for another Light Cavalry squadron were collected as a control. Both units were deployed in the same location, in the same role, and with the same population, fluctuating around 138 personnel.

Results

Between April and August 2020 there were 124 consultations for MSKI amongst the study population, this resulted in 241 days of restricted duties. In comparison for the control population (April to August 2019), there were 225 consultations for MSKI, and this resulted in 777 days of restricted duties.

Conclusions

It was found that the current unit has experienced a lower incidence of MSKI and fewer restricted duties days when compared to the control group. It is proposed that the greater emphasis on personal responsibility for physical fitness has allowed personnel to develop their fitness with a broader range of physical activity. This has resulted in a lesser burden of overuse injuries. It is also thought that the focus on personal responsibility has led to a greater desire to engage in physical training. Further work is needed to ensure that this trend continues throughout the operational tour and that the empowered training programme has a comparable benefit in physical fitness to the standard training program.
3 Clinical implications of the differential antibody response in mild-moderate SARS-CoV-2: a prospective multi-centre cross-sectional study
Authors: Pallett Scott , Jones Rachael , Rayment Michael , Pallett Mitchell A , Mughal Nabeela , Oliveira Carolina Rosadas de , Randell Paul , Davies Gary W , Tedder Richard , McClure Myra O , O’Shea Matthew K , Moore Luke SP
Published: May 2021

Introduction

Serological testing can augment delayed case identification programmes for Severe Acute Respiratory Syndrome coronoravirus-2 (SARS-CoV-2). Immunoassays employ anti-nucleocapsid (anti-NP; the majority) or potentially neutralising anti-spike (including anti-receptor binding domain; anti-RBD) antibody targets, yet correlation between assays and variability arising from disease symptomatology remains unclear. We explore these possibly differential immune responses across the disease spectrum.

Methods

A multicentre prospective study was undertaken via a SARS-CoV-2 delayed case identification programme (08 May-11 July 2020). Matched samples were tested for anti-NP and anti-RBD (utilising an ‘inhouse’ double-antigen bridged assay), reactivity expressed as test/cut-off binding ratios (BR) and results compared. A multivariate linear regression model analysed age, sex, symptomatology, PCR positivity, anti-NP, and anti-RBD BRs. Participants were followed up for possible reinfection.

Results

902 individuals underwent matched testing; 109 were SARS-CoV-2 PCR swab positive. Anti-NP, anti-RBD immunoassay agreement was 87.5% (95% CI 85.3–89.6), with BRs strongly correlated (R=0.75). PCR confirmed cases were more frequently identified by anti-RBD (sensitivity 108/109, 99.1%, 95% CI 95.0–100.0) than anti-NP (102/109, 93.6%, 95% CI 87.2–97.4). Anti-RBD identified an additional 83/325 (25.5%) cases in those seronegative for anti-NP. Presence of anti-NP (p<0.0001), fever (p=0.005), or anosmia (p=0.002) were all significantly associated with an increased anti-RBD BR. Age was associated with reduced anti-RBD BR (p=0.052). Three cases with evidence of seroconversion (anti-RBD seropositive) presented with subsequent reactive PCR results, two of which coincided with first time onset of Public Heath England SARS-CoV-2 symptoms.

Conclusions

SARS-CoV-2 anti-RBD shows significant correlation with anti-NP for absolute seroconversion, and BRs. Higher BRs are seen in symptomatic individuals with significantly higher levels seen in those with fever and anosmia. The degree of discordant results (12.5%) limits the use of anti-NP as a stand-alone for delayed case finding programmes. Similarly, this discordance limits the utility of non-neutralising anti-NP assays in place of potentially neutralising anti-RBD to infer possible immunity.

** this abstract presentation was awarded an Honourable Mention
4 Histamine, mast cell tryptase and post-exercise hypotension in healthy and collapsed marathon runners
Authors: Parsons Iain , Stacey Michael , Woods David
Published: May 2021

Introduction

Heat stress exacerbates post-exercise hypotension and cardiovascular disturbances from elevated body temperature and may contribute to exertion-related incapacity. Mast cell degranulation and muscle mass are considered likely modifiers, though this hypothesis lacks practical evidence. This study had three aims: 1) to characterise pre-post responses in histamine and mast cell tryptase (MCT); 2) to investigate relationships between whole body muscle mass (WBMM) and changes in blood pressure post marathon; 3) to identify any differences in runners incapacitated from marathon running.

Methods

24 recreational runners were recruited and successfully completed the 2019 Brighton Marathon (COMPLETION). WBMM was measured by bioimpedance at rested baseline. A further eight participants were recruited from incapacitated runners diagnosed with heat illness (COLLAPSE). Histamine, MCT, blood pressure, heart rate, body temperature and echocardiographic measures were taken before and after exercise (COMPLETION) and upon hyperthermic incapacitation (COLLAPSE).

Results

In COMPLETION, MCT increased by nearly 50% from baseline (p=0.001), whereas histamine and body temperature did not vary (P>0.9462). Systolic (sBP), diastolic (dBP) and mean (MAP) arterial blood pressures and systemic vascular resistance (SVR) declined (p<0.019). WBMM negatively correlated with ΔsBP (r=-0.43, p=0.046). For COLLAPSE versus COMPLETION there were significant elevations in MCT (1769±244 ng/L vs 1179±431, p=0.001) and body temperature (39.8±1.3 vs 36.2±0.8°C, p<0.0001) with a non-significant rise in histamine (9.6±17.9μg/L vs 13.7±33.9, p=0.1074) and significantly lower MAP, dBP and SVR (p<0.0327).

Conclusions

These data support the hypothesis that mast cell degranulation is a vasodilatory mechanism underlying PEH and exercise associated collapse. The magnitude of PEH is inversely proportional to the muscle mass and enhanced by concomitant body heating.