bluuebunny/crossref_metadata_2025 huggingface dataset:
Source Mechanisms of Laboratory Earthquakes During Fault Nucleation and Formation
Authors: King Thomas , Vinciguerra Sergio , Burgess Jodi , Benson Philip , De Siena Luca
Published: March 2021

Abstract

Identifying deformation and pre‐failure mechanisms preceding faulting is key for fault mechanics and for interpreting precursors to fault rupture. This study presents the results of a new and robust derivation of first motion polarity focal mechanism solutions (FMS) applied to acoustic emission (AE). FMS are solved using a least squares minimization of the fit between projected polarity measurements and the deviatoric stress field induced by dilatational (T‐type), shearing (S‐type), and compressional (C‐type) sources. 4 × 10 cm cylindrical samples of Alzo Granite (AG, porosity <1%) and Darley Dale Sandstone (DDS, porosity ≈14%) underwent conventional triaxial tests in order to investigate the relationships between increasing confining pressure (5, 10, 20, and 40 MPa), deformation and failure mode, and role of microstructural features. Results highlight that S‐type events occur in very low numbers with poor spatial correlation to fault structure. Instead, deformation is driven by a complex interplay between compactant (C‐type) and dilatant (T‐type) regions of deformation. C‐type events are the earliest precursor related to crack nucleation and T‐type events mark new cracks opening, with the onset of fracture growth characterized by periodic cycles of coalescence. For AG a single sequence is able to lead to dynamic failure, while for DDS several cycles are needed for coalescence to take place due to the competition between dilatant and compactant deforming regions induced by multiple fracture nucleation sites. The occurrence of C‐ and S‐type events is also consistent with a quasi‐static premonitory phase, or foreshock, before a critical nucleation length allows the development of a planar localization.
Year‐Round and Long‐Term Phytoplankton Dynamics in Lake Bonney, a Permanently Ice‐Covered Antarctic Lake
Authors: Patriarche J. D. , Priscu J. C. , Takacs‐Vesbach C. , Winslow L. , Myers K. F. , Buelow H. , Morgan‐Kiss R. M. , Doran P. T.
Published: March 2021

Lake Bonney (McMurdo Dry Valleys, east Antarctica) represents a year‐round refugium for life adapted to permanent extreme conditions. Despite intensive research since the 1960s, due to the logistical constraints posed by 4‐months of 24‐h darkness, knowledge of how the resident photosynthetic microorganisms respond to the polar winter is limited. In addition, the lake level has risen by more than 3 m since 2004: impacts of rapid lake level rise on phytoplankton community structure is also poorly understood. From 2004 to 2015 an in situ submersible spectrofluorometer (bbe FluoroProbe) was deployed in Lake Bonney during the austral summer to quantify the vertical structure of four functional algal groups (green algae, mixed algae, and cryptophytes, cyanobacteria). During the 2013–2014 field season the Fluoroprobe was mounted on autonomous cable‐crawling profilers deployed in both the east and west lobes of Lake Bonney, obtaining the first daily phytoplankton profiles through the polar night. Our findings showed that phytoplankton communities were differentially impacted by physical and chemical factors over long‐term versus seasonal time scales. Following a summer of rapid lake level rise (2010–2011), an increase in depth integrated chlorophyll a (chl‐a) occurred in Lake Bonney caused by stimulation of photoautotrophic green algae. Conversely, peaks in chl‐a during the polar night were associated with an increase in mixotrophic haptophytes and cryptophytes. Collectively our data reveal that phytoplankton groups possessing variable trophic abilities are differentially competitive during seasonal and long‐term time scales owing to periods of higher nutrients (photoautotrophs) versus light/energy limitation (mixotrophs).
Strengthening Atlantic Inflow Across the Mid‐Pleistocene Transition
Authors: Barker Stephen , Zhang Xu , Jonkers Lukas , Lordsmith Sian , Conn Stephen , Knorr Gregor
Published: March 2021

The development of larger and longer lasting northern hemisphere ice sheets during the mid‐Pleistocene Transition (MPT) coincided with global cooling. Here, we show that surface waters of the north‐eastern Atlantic actually warmed across this interval (∼1.2–0.8 Ma), which we argue reflects an increase in the north‐eastward transport of heat and moisture via the North Atlantic Current (NAC) into the Nordic Seas (the Atlantic Inflow). We suggest that simultaneous cooling and warming along the north‐western and south‐eastern margins (respectively) of the NAC during Marine Isotope Stage 28 (∼995 ka) reflected the increasing persistence of northern ice sheets as Atlantic Inflow increased. This resulted in a diachronous shift from ∼40 to ∼100 kyr cyclicity across the North East (NE) Atlantic as the growing influence of northern ice sheets spread southwards; to the north‐west of the NAC the first “100 kyr” cycle preceded Termination 12 (∼960 ka), while on the south‐eastern margin of the NAC the transition occurred ∼100 kyr later. Exploratory climate model simulations suggest that increasing Atlantic Inflow at this time could have accelerated ice sheet growth because pre‐existing moderately sized ice sheets allowed the positive effect of increasing precipitation to outpace melting. In addition, we propose that the dependence of post‐MPT ice sheets on moisture transport via the Atlantic Inflow may ultimately contribute to their apparent vulnerability to insolation forcing once a critical size threshold is crossed and high latitude ice sheets become starved of a vital moisture source.
Molecular bridge-mediated ultralow-power gas sensing
Authors: Banerjee Aishwaryadev , Khan Shakir-Ul Haque , Broadbent Samuel , Bulbul Ashrafuzzaman , Kim Kyeong Heon , Noh Seungbeom , Looper R. , Mastrangelo C. H. , Kim H.
Published: March 2021

We report the electrical detection of captured gases through measurement of the quantum tunneling characteristics of gas-mediated molecular junctions formed across nanogaps. The gas-sensing nanogap device consists of a pair of vertically stacked gold electrodes separated by an insulating 6 nm spacer (~1.5 nm of sputtered α-Si and ~4.5 nm ALD SiO2), which is notched ~10 nm into the stack between the gold electrodes. The exposed gold surface is functionalized with a self-assembled monolayer (SAM) of conjugated thiol linker molecules. When the device is exposed to a target gas (1,5-diaminopentane), the SAM layer electrostatically captures the target gas molecules, forming a molecular bridge across the nanogap. The gas capture lowers the barrier potential for electron tunneling across the notched edge region, from ~5 eV to ~0.9 eV and establishes additional conducting paths for charge transport between the gold electrodes, leading to a substantial decrease in junction resistance. We demonstrated an output resistance change of >108 times upon exposure to 80 ppm diamine target gas as well as ultralow standby power consumption of <15 pW, confirming electron tunneling through molecular bridges for ultralow-power gas sensing.
Variable influences of soil and seed-associated bacterial communities on the assembly of seedling microbiomes
Authors: Walsh Corinne M , Becker-Uncapher Isadore , Carlson Madeline , Fierer Noah
Published: March 2021

Plants grown in distinct soils typically harbor distinct microbial communities, but the degree of the soil microbiome influence on plant microbiome assembly remains largely undetermined. We also know that the microbes associated with seeds can contribute to the plant microbiome, but the magnitude of this contribution is likely variable. We quantified the influence of soil and seed microbiomes on the bacterial community composition of seedlings by independently inoculating seeds from a single cultivar of wheat (Triticum aestivum) with 219 unique soil slurries while holding other environmental factors constant, determining the composition of the seed, soil, and seedling bacterial communities via cultivation-independent methods. Soil bacterial communities exert a strong, but variable, influence on seedling bacterial community structure, with the extent of the soil bacterial contribution dependent on the soil in question. By testing a wide range of soils, we were able to show that the specific composition of the seedling microbiome is predictable from knowing which bacterial taxa are found in soil. Although the most ubiquitous taxa associated with the seedlings were seed derived, the contributions of the seed microbiome to the seedling microbiome were variable and dependent on soil bacterial community composition. Together this work improves our predictive understanding of how the plant microbiome assembles and how the seedling microbiome could be directly or indirectly manipulated to improve plant health.
GABA signalling modulates stomatal opening to enhance plant water use efficiency and drought resilience
Authors: Xu Bo , Long Yu , Feng Xueying , Zhu Xujun , Sai Na , Chirkova Larissa , Betts Annette , Herrmann Johannes , Edwards Everard J. , Okamoto Mamoru , Hedrich Rainer , Gilliham Matthew
Published: March 2021

The non-protein amino acid γ-aminobutyric acid (GABA) has been proposed to be an ancient messenger for cellular communication conserved across biological kingdoms. GABA has well-defined signalling roles in animals; however, whilst GABA accumulates in plants under stress it has not been determined if, how, where and when GABA acts as an endogenous plant signalling molecule. Here, we establish endogenous GABA as a bona fide plant signal, acting via a mechanism not found in animals. Using Arabidopsis thaliana, we show guard cell GABA production is necessary and sufficient to reduce stomatal opening and transpirational water loss, which improves water use efficiency and drought tolerance, via negative regulation of a stomatal guard cell tonoplast-localised anion transporter. We find GABA modulation of stomata occurs in multiple plants, including dicot and monocot crops. This study highlights a role for GABA metabolism in fine tuning physiology and opens alternative avenues for improving plant stress resilience.
The SARS-CoV-2 nucleocapsid protein is dynamic, disordered, and phase separates with RNA
Authors: Cubuk Jasmine , Alston Jhullian J. , Incicco J. Jeremías , Singh Sukrit , Stuchell-Brereton Melissa D. , Ward Michael D. , Zimmerman Maxwell I. , Vithani Neha , Griffith Daniel , Wagoner Jason A. , Bowman Gregory R. , Hall Kathleen B. , Soranno Andrea , Holehouse Alex S.
Published: March 2021

The SARS-CoV-2 nucleocapsid (N) protein is an abundant RNA-binding protein critical for viral genome packaging, yet the molecular details that underlie this process are poorly understood. Here we combine single-molecule spectroscopy with all-atom simulations to uncover the molecular details that contribute to N protein function. N protein contains three dynamic disordered regions that house putative transiently-helical binding motifs. The two folded domains interact minimally such that full-length N protein is a flexible and multivalent RNA-binding protein. N protein also undergoes liquid-liquid phase separation when mixed with RNA, and polymer theory predicts that the same multivalent interactions that drive phase separation also engender RNA compaction. We offer a simple symmetry-breaking model that provides a plausible route through which single-genome condensation preferentially occurs over phase separation, suggesting that phase separation offers a convenient macroscopic readout of a key nanoscopic interaction.
Measuring 3D orientation of nanocrystals via polarized luminescence of rare-earth dopants
Authors: Kim Jeongmo , Chacón Reinaldo , Wang Zijun , Larquet Eric , Lahlil Khalid , Leray Aymeric , Colas-des-Francs Gérard , Kim Jongwook , Gacoin Thierry
Published: March 2021

Orientation of nanoscale objects can be measured by examining the polarized emission of optical probes. To retrieve a three-dimensional (3D) orientation, it has been essential to observe the probe (a dipole) along multiple viewing angles and scan with a rotating analyzer. However, this method requires a sophisticated optical setup and is subject to various external sources of error. Here, we present a fundamentally different approach employing coupled multiple emission dipoles that are inherent in lanthanide-doped phosphors. Simultaneous observation of different dipoles and comparison of their relative intensities allow to determine the 3D orientation from a single viewing angle. Moreover, the distinct natures of electric and magnetic dipoles originating in lanthanide luminescence enable an instant orientation analysis with a single-shot emission spectrum. We demonstrate a straightforward orientation analysis of Eu3+-doped NaYF4 nanocrystals using a conventional fluorescence microscope. Direct imaging of the rod-shaped nanocrystals proved the high accuracy of the measurement. This methodology would provide insights into the mechanical behaviors of various nano- and biomolecular systems.
The folate cycle enzyme MTHFD2 induces cancer immune evasion through PD-L1 up-regulation
Authors: Shang Man , Yang Huijie , Yang Ran , Chen Tao , Fu Yuan , Li Yeyi , Fang Xianlong , Zhang Kangjian , Zhang Jianju , Li Hui , Cao Xueping , Gu Jinfa , Xiao Jianwen , Zhang Qi , Liu Xinyuan , Yu Qiujing , Wang Ting
Published: March 2021

Metabolic enzymes and metabolites display non-metabolic functions in immune cell signalling that modulate immune attack ability. However, whether and how a tumour’s metabolic remodelling contributes to its immune resistance remain to be clarified. Here we perform a functional screen of metabolic genes that rescue tumour cells from effector T cell cytotoxicity, and identify the embryo- and tumour-specific folate cycle enzyme methylenetetrahydrofolate dehydrogenase 2 (MTHFD2). Mechanistically, MTHFD2 promotes basal and IFN-γ-stimulated PD-L1 expression, which is necessary for tumourigenesis in vivo. Moreover, IFN-γ stimulates MTHFD2 through the AKT–mTORC1 pathway. Meanwhile, MTHFD2 drives the folate cycle to sustain sufficient uridine-related metabolites including UDP-GlcNAc, which promotes the global O-GlcNAcylation of proteins including cMYC, resulting in increased cMYC stability and PD-L1 transcription. Consistently, the O-GlcNAcylation level positively correlates with MTHFD2 and PD-L1 in pancreatic cancer patients. These findings uncover a non-metabolic role for MTHFD2 in cell signalling and cancer biology.
An ecological approach to structural flexibility in online communication systems
Authors: Palazzi María J. , Solé-Ribalta Albert , Calleja-Solanas Violeta , Meloni Sandro , Plata Carlos A. , Suweis Samir , Borge-Holthoefer Javier
Published: March 2021

Human cognitive abilities are limited resources. Today, in the age of cheap information—cheap to produce, to manipulate, to disseminate—this cognitive bottleneck translates into hypercompetition for rewarding outcomes among actors. These incentives push actors to mutualistically interact with specific memes, seeking the virality of their messages. In turn, memes’ chances to persist and spread are subject to changes in the communication environment. In spite of all this complexity, here we show that the underlying architecture of empirical actor-meme information ecosystems evolves into recurring emergent patterns. We then propose an ecology-inspired modelling framework, bringing to light the precise mechanisms causing the observed flexible structural reorganisation. The model predicts—and the data confirm—that users’ struggle for visibility induces a re-equilibration of the network’s mesoscale towards self-similar nested arrangements. Our final microscale insights suggest that flexibility at the structural level is not mirrored at the dynamical one.
Implications of the school-household network structure on SARS-CoV-2 transmission under school reopening strategies in England
Authors: Munday James D. , Sherratt Katharine , Meakin Sophie , Endo Akira , Pearson Carl A. B. , Hellewell Joel , Abbott Sam , Bosse Nikos I. ,   CMMID COVID-19 Working Group, Eggo Rosalind M. , Simons David , O’Reilly Kathleen , Russell Timothy W. , Lowe Rachel , Leclerc Quentin J. , Emery Jon C. , Klepac Petra , Nightingale Emily S. , Quaife Matthew , van Zandvoort Kevin , Knight Gwenan M. , Jombart Thibaut , Villabona-Arenas C. Julian , Rees Eleanor M. , Diamond Charlie , Auzenbergs Megan , Medley Graham , Foss Anna M. , Gore-Langton Georgia R. , Deol Arminder K. , Jit Mark , Gibbs Hamish P. , Procter Simon R. , Rosello Alicia , Jarvis Christopher I. , Liu Yang , Houben Rein M. G. J. , Hué Stéphane , Clifford Samuel , Quilty Billy J. , Gimma Amy , Tully Damien C. , Sun Fiona Yueqian , Prem Kiesha , Atkins Katherine E. , Wallinga Jacco , Edmunds W. John , van Hoek Albert Jan , Funk Sebastian
Published: March 2021

In early 2020 many countries closed schools to mitigate the spread of SARS-CoV-2. Since then, governments have sought to relax the closures, engendering a need to understand associated risks. Using address records, we construct a network of schools in England connected through pupils who share households. We evaluate the risk of transmission between schools under different reopening scenarios. We show that whilst reopening select year-groups causes low risk of large-scale transmission, reopening secondary schools could result in outbreaks affecting up to 2.5 million households if unmitigated, highlighting the importance of careful monitoring and within-school infection control to avoid further school closures or other restrictions.
Recent global decrease in the inner-core rain rate of tropical cyclones
Authors: Tu Shifei , Xu Jianjun , Chan Johnny C. L. , Huang Kian , Xu Feng , Chiu Long S.
Published: March 2021

Heavy rainfall is one of the major aspects of tropical cyclones (TC) and can cause substantial damages. Here, we show, based on satellite observational rainfall data and numerical model results, that between 1999 and 2018, the rain rate in the outer region of TCs has been increasing, but it has decreased significantly in the inner-core. Globally, the TC rain rate has increased by 8 ± 4% during this period, which is mainly contributed by an increase in rain rate in the TC outer region due to increasing water vapor availability in the atmosphere with rising surface temperature. On the other hand, the rain rate in the inner-core of TCs has decreased by 24 ± 3% during the same period. The decreasing trend in the inner-core rain rate likely results mainly from an increase in atmospheric stability.
Classical magnetic vortex liquid and large thermal Hall conductivity in frustrated magnets with bond-dependent interactions
Authors: Chern Li Ern , Buessen Finn Lasse , Kim Yong Baek
Published: March 2021

Recently, the observation of large thermal Hall conductivities in correlated insulators with no apparent broken symmetry has generated immense interest and debates on the underlying ground states. Here, considering frustrated magnets with bond-dependent interactions, which are realized in the so-called Kitaev materials, we theoretically demonstrate that a large thermal Hall conductivity can originate from a classical ground state without any magnetic order. We discover a liquid state of magnetic vortices, which are inhomogeneous spin textures embedded in the background of polarized spins, under out-of-plane magnetic fields. In the classical regime, different configurations of vortices form an effectively degenerate manifold. We study the static and dynamical properties of the magnetic vortex liquid state at zero and finite temperatures. In particular, we show that the spin excitation spectrum resembles a continuum of nearly flat Chern bands, which ultimately leads to a large thermal Hall conductivity. Possible connections to experiments are discussed.
Severity of heterosubtypic influenza virus infection in ferrets is reduced by live attenuated influenza vaccine
Authors: Marriott Anthony C. , Gooch Karen E. , Brown Phillip J. , Ryan Kathryn A. , Jones Nicola J. , Merredew Natasha , Wiblin Nathan , Dibben Oliver , Bright Helen , Hallis Bassam , Whittaker Catherine J. , Carroll Miles W.
Published: March 2021

Live attenuated influenza vaccine (LAIV) is widely used to protect humans from seasonal influenza infection, particularly in children. In contrast to inactivated vaccines, the LAIV can induce both mucosal and cellular immune responses. Here we show that a single dose of monovalent H1N1pdm09-specific LAIV in the ferret model is fully protective against a subsequent wild-type H1N1pdm09 challenge, and furthermore reduces the severity of disease following challenge with a different influenza A subtype (H3N2). The reduced severity comprised reductions in weight loss and fever, as well as more rapid clearance of virus, compared to non-vaccinated H3N2-challenged ferrets. No H3N2-neutralizing antibodies were detected in vaccinated ferret sera. Rather, heterosubtypic protection correlated with interferon-gamma+ (IFN-γ+) T-cell responses measured in peripheral blood and in lung lymphocytes. The IFN-γ+ cells were cross-reactive to H3N2 virus even when obtained from vaccinated animals that had never been exposed to H3N2 virus. We believe this study provides compelling evidence that the LAIV can provide a significant reduction in infection and symptoms when challenged with heterosubtypic influenza strains not included in the LAIV, highlighting the importance of cross-reactive T-cells in the design of a universal influenza vaccine.
Environmental evolution, faunal and human occupation since 2 Ma in the Anagni basin, central Italy
Authors: Florindo Fabio , Marra Fabrizio , Angelucci Diego E. , Biddittu Italo , Bruni Luciano , Florindo Federico , Gaeta Mario , Guillou Hervé , Jicha Brian , Macrì Patrizia , Morigi Caterina , Nomade Sebastien , Parenti Fabio , Pereira Alison , Grimaldi Stefano
Published: March 2021

We present the study of a composite, yet continuous sedimentary succession covering the time interval spanning 2.6–0.36 Ma in the intramontane basin of Anagni (central Italy) through a dedicated borecore, field surveys, and the review of previous data at the three palaeontological and archaeological sites of Colle Marino, Coste San Giacomo and Fontana Ranuccio. By combining the magneto- and chronostratigraphic data with sedimentologic and biostratigraphic analysis, we describe the palaeogeographic and tectonic evolution of this region during this entire interval. In this time frame, starting from 0.8 Ma, the progressive shallowing and temporary emersion of the large lacustrine basins and alluvial plains created favorable conditions for early hominin occupation of the area, as attested by abundant tool industry occurrences and fossils. This study provides new constraints to better interpret the hominin migratory dynamics and the factors that influenced the location and spatial distribution during the early occupation of this region.
Compensatory image of the stability of people with multiple sclerosis and atrial vertigo based on posturography examination
Authors: Kahl Oliwer , Wierzbicka Ewelina , Dębińska Magdalena , Mraz Maciej , Mraz Małgorzata
Published: March 2021

Pathophysiology of balance disorders due to multiple sclerosis (MS) and atrial vertigo (AV) is different. We evaluated posture stability when maintaining balance in people with MS presenting symptoms of ataxia and those with AV. We included 45 women (15 with MS; 15 with AV; 15 controls). A posturography platform was used to measure balance parameters. To characterize the image of stability and the compensation of balance disorders, the surface area of the stabilogram (SAS), vision control index (VCI) and the vision-motion control index (VMCI) were used. The stability image of people with MS and AV with eyes open (p = 0.002), with eyes closed (p = 0.080) and with visual biofeedback (p = 0.0008) differed significantly. SAS depended on visual biofeedback regardless of the occurrence of balance disorders and was the basis for determining the compensatory share of vision-motor coordination. Differences in VCI between groups were insignificant. VMCI was significantly higher in people with balance disorders than in those without, but similar in the MS and AV groups. The image of stability is different in people with MS and AV. Thanks to visual biofeedback, it becomes possible to launch effective vision-motor coordination when compensating balance disorders. VCI may become the measure of compensation for balance disorders.
Metformin ameliorates the severity of experimental Alport syndrome
Authors: Omachi Kohei , Kaseda Shota , Yokota Tsubasa , Kamura Misato , Teramoto Keisuke , Kuwazuru Jun , Kojima Haruka , Nohara Hirofumi , Koyama Kosuke , Ohtsuki Sumio , Misumi Shogo , Takeo Toru , Nakagata Naomi , Li Jian-Dong , Shuto Tsuyoshi , Suico Mary Ann , Miner Jeffrey H. , Kai Hirofumi
Published: March 2021

Metformin is widely used for the treatment of type 2 diabetes, and increasing numbers of studies have shown that metformin also ameliorates tumor progression, inflammatory disease, and fibrosis. However, the ability of metformin to improve non-diabetic glomerular disease and chronic kidney disease (CKD) has not been explored. To investigate the effect of metformin on non-diabetic glomerular disease, we used a mouse model of Alport syndrome (Col4a5 G5X) which were treated with metformin or losartan, used as a control treatment. We also investigated the effect of metformin on adriamycin-induced glomerulosclerosis model. Pathological and biochemical analysis showed that metformin or losartan suppressed proteinuria, renal inflammation, fibrosis, and glomerular injury and extended the lifespan in Alport syndrome mice. Transcriptome analysis showed that metformin and losartan influenced molecular pathways-related to metabolism and inflammation. Metformin altered multiple genes including metabolic genes not affected by losartan. Metformin also suppressed proteinuria and glomerular injury in the adriamycin-induced glomerulosclerosis mouse model. Our results showed that metformin ameliorates the glomerular sclerosis and CKD phenotype in non-diabetic chronic glomerular diseases. Metformin may have therapeutic potential for not only diabetic nephropathy but also non-diabetic glomerular disease including Alport syndrome.
Quantitative probe for in-plane piezoelectric coupling in 2D materials
Authors: Yarajena Sai Saraswathi , Biswas Rabindra , Raghunathan Varun , Naik Akshay K.
Published: March 2021

Piezoelectric response in two-dimensional (2D) materials has evoked immense interest in using them for various applications involving electromechanical coupling. In most of the 2D materials, piezoelectricity is coupled along the in-plane direction. Here, we propose a technique to probe the in-plane piezoelectric coupling strength in layered nanomaterials quantitively. The method involves a novel approach for in-plane field excitation in lateral Piezoresponse force microscopy (PFM) for 2D materials. Operating near contact resonance has enabled the measurement of the piezoelectric coupling coefficients in the sub pm/V range. Detailed methodology for the signal calibration and the background subtraction when PFM is operated near the contact resonance of the cantilever is also provided. The technique is verified by estimating the in-plane piezoelectric coupling coefficients (d11) for freely suspended MoS2 of one to five atomic layers. For 2D-MoS2 with the odd number of atomic layers, which are non-centrosymmetric, finite d11 is measured. The measurements also indicate that the coupling strength decreases with an increase in the number of layers. The techniques presented would be an effective tool to study the in-plane piezoelectricity quantitatively in various materials along with emerging 2D-materials.
Comparison of different protocols for demineralization of cortical bone
Authors: Pang Siyuan , Su Frances Y. , Green Amesha , Salim Justin , McKittrick Joanna , Jasiuk Iwona
Published: March 2021

Bone is a biological composite material consisting of two main components: collagen and mineral. Collagen is the most abundant protein in vertebrates, which makes it of high clinical and scientific interest. In this paper, we compare the composition and structure of cortical bone demineralized using several protocols: ethylene-diamine-tetraacetic acid (EDTA), formic acid (CH2O2), hydrochloric acid (HCl), and HCl/EDTA mixture. The efficiencies of these four agents were investigated by assessing the remaining mineral quantities and collagen integrity with various experimental techniques. Raman spectroscopy results show that the bone demineralized by the CH2O2agent has highest collagen quality parameter. The HCl/EDTA mixture removes the most mineral, but it affects the collagen secondary structure as amide II bands are shifted as observed by Fourier transform infrared spectroscopy. Thermogravimetric analysis reveals that HCl and EDTA are most effective in removing the mineral with bulk measurements. In summary, we conclude that HCl best demineralizes bone, leaving the well-preserved collagen structure in the shortest time. These findings guide on the best demineralization protocol to obtain high-quality collagen from bone for clinical and scientific applications.
Analysis of temporal trends in potential COVID-19 cases reported through NHS Pathways England
Authors: Leclerc Quentin J. , Nightingale Emily S. , Abbott Sam ,   CMMID COVID-19 Working Group, Rees Eleanor M. , Eggo Rosalind M. , Quaife Matthew , Sun Fiona Yueqian , Pearson Carl A. B. , Prem Kiesha , Munday James D. , Meakin Sophie R. , Medley Graham , van Zandvoort Kevin , Edmunds W. John , Rosello Alicia , Funk Sebastian , O’Reilly Kathleen , Quilty Billy J. , Procter Simon R. , Gimma Amy , Kucharski Adam J. , Deol Arminder K. , Emery Jon C. , Bosse Nikos I. , Gibbs Hamish P. , Simons David , Hué Stéphane , Jarvis Christopher I. , Klepac Petra , Liu Yang , Foss Anna M. , Diamond Charlie , Villabona-Arenas C. Julian , Endo Akira , Houben Rein M. G. J. , Flasche Stefan , Russell Timothy W. , Clifford Samuel , Knight Gwenan M. , Hellewell Joel , Davies Nicholas G. , Atkins Katherine E. , Tully Damien C. , Auzenbergs Megan , Jit Mark , Lowe Rachel , Jombart Thibaut
Published: March 2021

The National Health Service (NHS) Pathways triage system collates data on enquiries to 111 and 999 services in England. Since the 18th of March 2020, these data have been made publically available for potential COVID-19 symptoms self-reported by members of the public. Trends in such reports over time are likely to reflect behaviour of the ongoing epidemic within the wider community, potentially capturing valuable information across a broader severity profile of cases than hospital admission data. We present a fully reproducible analysis of temporal trends in NHS Pathways reports until 14th May 2020, nationally and regionally, and demonstrate that rates of growth/decline and effective reproduction number estimated from these data may be useful in monitoring transmission. This is a particularly pressing issue as lockdown restrictions begin to be lifted and evidence of disease resurgence must be constantly reassessed. We further assess the correlation between NHS Pathways reports and a publicly available NHS dataset of COVID-19-associated deaths in England, finding that enquiries to 111/999 were strongly associated with daily deaths reported 16 days later. Our results highlight the potential of NHS Pathways as the basis of an early warning system. However, this dataset relies on self-reported symptoms, which are at risk of being severely biased. Further detailed work is therefore necessary to investigate potential behavioural issues which might otherwise explain our conclusions.
A microfabricated multi-compartment device for neuron and Schwann cell differentiation
Authors: De Vitis Eleonora , La Pesa Velia , Gervaso Francesca , Romano Alessandro , Quattrini Angelo , Gigli Giuseppe , Moroni Lorenzo , Polini Alessandro
Published: March 2021

Understanding the complex communication between different cell populations and their interaction with the microenvironment in the central and peripheral nervous systems is fundamental in neuroscience research. The development of appropriate in vitro approaches and tools, able to selectively analyze and/or probe specific cells and cell portions (e.g., axons and cell bodies in neurons), driving their differentiation into specific cell phenotypes, has become therefore crucial in this direction. Here we report a multi-compartment microfluidic device where up to three different cell populations can be cultured in a fluidically independent circuit. The device allows cell migration across the compartments and their differentiation. We showed that an accurate choice of the device geometrical features and cell culture parameters allows to (1) maximize cell adhesion and proliferation of neuron-like human cells (SH-SY5Y cells), (2) control the inter-compartment cell migration of neuron and Schwann cells, (3) perform long-term cell culture studies in which both SH-SY5Y cells and primary rat Schwann cells can be differentiated towards specific phenotypes. These results can lead to a plethora of in vitro co-culture studies in the neuroscience research field, where tuning and investigating cell–cell and cell–microenvironment interactions are essential.
Aqueductal CSF stroke volume measurements may drive management of shunted idiopathic normal pressure hydrocephalus patients
Authors: Scollato Antonio , Caini Saverio , Angelini Lucia , Lastrucci Giancarlo , Di Lorenzo Nicola , Porfirio Berardino , Gallina Pasquale
Published: March 2021

CSF shunting with adjustable valve is the treatment of idiopathic normal pressure hydrocephalus. The opening pressure valve setting is left to the neurosurgeon’s experience. Aqueductal CSF stroke volume by phase-contrast magnetic resonance measures the CSF passing through the Sylvian aqueduct and it changes with intracranial hydrodynamics. We sought to identify a window of stroke volume differences associated with the best clinical outcome and lowest rate of complications.
The records of 69 patients were reviewed. At every clinical check, stroke volume, opening pressure valve, clinical outcome, and CSF overdrainage were analyzed. The correlation between stroke volume differences and negative outcome was also analyzed. The median follow-up was 2.3 years (range 0.3–10.4 years). The odds of negative outcome between two consecutive checks significantly increased by 16% (95%CI 4–28%, p = 0.006). Taking the lowest risk group as reference, the odds ratio of negative outcome was 1.16 (95%CI 0.51–2.63, p = 0.726) for SV differences less than − 37.6 µL, while it was 1.96 (95%CI 0.97–3.98, p = 0.062) for stroke volume changes above + 23.1 µL. Maintaining stroke volume values within a definite range might help maximize clinical benefit and avoid the risk of CSF overdrainage.
Exploring new roles for actin upon LTP induction in dendritic spines
Authors: Bonilla-Quintana Mayte , Wörgötter Florentin
Published: March 2021

Dendritic spines, small protrusions of the dendrites, enlarge upon LTP induction, linking morphological and functional properties. Although the role of actin in spine enlargement has been well studied, little is known about its relationship with mechanical membrane properties, such as membrane tension, which is involved in many cell processes, like exocytosis. Here, we use a 3D model of the dendritic spine to investigate how polymerization of actin filaments can effectively elevate the membrane tension to trigger exocytosis in a domain close to the tip of the spine. Moreover, we show that the same pool of actin promotes full membrane fusion after exocytosis and spine stabilization.
Lock-in vibration retrieval based on high-speed full-field coherent imaging
Authors: Meteyer Erwan , Montresor Silvio , Foucart Felix , Le Meur Julien , Heggarty Kevin , Pezerat Charles , Picart Pascal
Published: March 2021

The use of high-speed cameras permits to visualize, analyze or study physical phenomena at both their time and spatial scales. Mixing high-speed imaging with coherent imaging allows recording and retrieving the optical path difference and this opens the way for investigating a broad variety of scientific challenges in biology, medicine, material science, physics and mechanics. At high frame rate, simultaneously obtaining suitable performance and level of accuracy is not straightforward. In the field of mechanics, this prevents high-speed imaging to be applied to full-field vibrometry. In this paper, we demonstrate a coherent imaging approach that can yield full-field structural vibration measurements with state-of-the-art performances in case of high spatial and temporal density measurements points of holographic measurement. The method is based on high-speed on-line digital holography and recording a short time sequence. Validation of the proposed approach is carried out by comparison with a scanning laser Doppler vibrometer and by realistic simulations. Several error criteria demonstrate measurement capability of yielding amplitude and phase of structural deformations.
Liquiñe-Ofqui’s fast slipping intra-volcanic arc crustal faulting above the subducted Chile Ridge
Authors: De Pascale Gregory P. , Froude Melanie , Penna Ivanna , Hermanns Reginald L. , Sepúlveda Sergio A. , Moncada Daniel , Persico Mario , Easton Gabriel , Villalobos Angelo , Gutiérrez Francisco
Published: March 2021

The southernmost portion of the Liquiñe-Ofqui fault zone (LOFZ) lies within the proposed slab window which formed due to oblique subduction of the Chile Ridge in Patagonia. Mapping of paleo-surface ruptures, offsets, and lithological separations along the master fault allowed us to constrain geologic slip rates for the first time with dextral rates of 11.6–24.6 mm/year (Quaternary) and 3.6–18.9 mm/year (Late-Cenozoic) respectively. We had trouble mapping the LOFZ in one local because of a partially collapsed and previously undiscovered volcanic complex, Volcan Mate Grande (VMG: 1,280 m high and thus Vesuvius-sized) that grew in a caldera also offset along the LOFZ and has distinct geochemistry from adjacent stratovolcanoes. Besides the clear seismic and volcanic hazard implications, the structural connection along the main trace of the fast slipping LOFZ and geochemistry of VMG provides evidence for the slab window and insight into interplay between fast-slipping crustal intra-arc crustal faults and volcanoes.
Fractal-induced 2D flexible net undulation
Authors: Goh Michael Joon Seng , Chiew Yeong Shiong , Foo Ji Jinn
Published: March 2021

A net immersed in fractal-induced turbulence exhibit a transient time-varying deformation. The anisotropic, inhomogeneous square fractal grid (SFG) generated flow interacts with the flexible net to manifest as visible cross-sectional undulations. We hypothesize that the net’s response may provide a surrogate in expressing local turbulent strength. This is analysed as root-mean-squared velocity fluctuations in the net, displaying intensity patterns dependent on the grid conformation and grid-net separation. The net’s fluctuation strength is found to increase closer to the turbulator with higher thickness ratio while presenting stronger fluctuations compared to regular-square-grid (RSG) of equivalent blockage-ratio,σ. Our findings demonstrate a novel application where 3D-reconstruction of submerged nets is used to experimentally contrast the turbulence generated by RSG and multilength scale SFGs across the channel cross-section. The net’s response shows the unique turbulence developed from SFGs can induce 9 × higher average excitation to a net when compared against RSG of similarσ.
Systematic review and meta-analysis of female lifestyle factors and risk of recurrent pregnancy loss
Authors: Ng Ka Ying Bonnie , Cherian George , Kermack Alexandra J. , Bailey Sarah , Macklon Nick , Sunkara Sesh K. , Cheong Ying
Published: March 2021

It is known that lifestyle factors affect sporadic miscarriage, but the extent of this on RPL (recurrent pregnancy loss) is less well known. A systematic review and meta-analysis was performed to assess the associations between lifestyle factors and RPL. Studies that analysed RPL in the context of BMI, smoking, alcohol and caffeine intake were included. The primary and secondary outcomes were odds of having RPL in the general population and odds of further miscarriage, respectively. Underweight and women with BMI > 25 are at higher odds of RPL in the general population (OR 1.2, 95% CI 1.12–1.28 and OR 1.21, 95% CI 1.06–1.38, respectively). In women with RPL, having BMI > 30 and BMI > 25 has increased odds of further miscarriages (OR 1.77, 95% CI 1.25–2.50 and OR 1.35, 95% CI 1.07–1.72, respectively). The quality of the evidence for our findings was low or very low. Being underweight and BMI > 25 contributes significantly to increased risk of RPL (general population). BMI > 25 or BMI > 30 increases the risk of further miscarriages (RPL population). Larger studies addressing the effects of alcohol, cigarette smoking and caffeine on the risk of RPL with optimisation of BMI in this cohort of women are now needed.
Hilbert–Schmidt speed as an efficient figure of merit for quantum estimation of phase encoded into the initial state of open n-qubit systems
Authors: Rangani Jahromi Hossein , Lo Franco Rosario
Published: March 2021

Hilbert–Schmidt speed (HSS) is a special type of quantum statistical speed which is easily computable, since it does not require diagonalization of the system state. We find that, when both HSS and quantum Fisher information (QFI) are calculated with respect to the phase parameter encoded into the initial state of an n-qubit register, the zeros of the HSS dynamics are actually equal to those of the QFI dynamics. Moreover, the signs of the time-derivatives of both HSS and QFI exactly coincide. These findings, obtained via a thorough investigation of several paradigmatic open quantum systems, show that HSS and QFI exhibit the same qualitative time evolution. Therefore, HSS reveals itself as a powerful figure of merit for enhancing quantum phase estimation in an open quantum system made of n qubits. Our results also provide strong evidence for both contractivity of the HSS under memoryless dynamics and its sensitivity to system-environment information backflows to detect the non-Markovianity in high-dimensional systems, as suggested in previous studies.
Temporal properties of higher-order interactions in social networks
Authors: Cencetti Giulia , Battiston Federico , Lepri Bruno , Karsai Márton
Published: March 2021

Human social interactions in local settings can be experimentally detected by recording the physical proximity and orientation of people. Such interactions, approximating face-to-face communications, can be effectively represented as time varying social networks with links being unceasingly created and destroyed over time. Traditional analyses of temporal networks have addressed mostly pairwise interactions, where links describe dyadic connections among individuals. However, many network dynamics are hardly ascribable to pairwise settings but often comprise larger groups, which are better described by higher-order interactions. Here we investigate the higher-order organizations of temporal social networks by analyzing five publicly available datasets collected in different social settings. We find that higher-order interactions are ubiquitous and, similarly to their pairwise counterparts, characterized by heterogeneous dynamics, with bursty trains of rapidly recurring higher-order events separated by long periods of inactivity. We investigate the evolution and formation of groups by looking at the transition rates between different higher-order structures. We find that in more spontaneous social settings, group are characterized by slower formation and disaggregation, while in work settings these phenomena are more abrupt, possibly reflecting pre-organized social dynamics. Finally, we observe temporal reinforcement suggesting that the longer a group stays together the higher the probability that the same interaction pattern persist in the future. Our findings suggest the importance of considering the higher-order structure of social interactions when investigating human temporal dynamics.
Effects of bioactive glass incorporation into glass ionomer cement on demineralized dentin
Authors: Kim Hyun-Jung , Bae Han Eul , Lee Ji-Eun , Park In-Seong , Kim Hee-Gyun , Kwon Jiyoung , Kim Duck-Su
Published: March 2021

The effects of the incorporation of sodium-free bioactive glass into glass ionomer cement (GIC) on the demineralized dentin are studied. Four experimental groups with various amounts of BAG in GIC were considered: BG0 group: 0 wt% (control); BG5 group: 5 wt%; BG10 group: 10 wt%; BG20 group: 20 wt%. The GIC surface and GIC-approximated demineralized dentin surfaces were evaluated using field emission scanning electron microscopy (FE–SEM). X-ray diffraction (XRD) analysis was performed to evaluate the chemical changes in the GIC-approximated dentin surface. In addition, a shear bond strength test was performed to evaluate the effects of BAG incorporation on the bond strength of GIC. FE–SEM analysis indicated that BAG-incorporated GICs formed distinct precipitates on their surface. Precipitates were also formed on the GIC-approximated demineralized dentin surface. It was more obvious when the amount of BAG increased. In the XRD analysis, fluorapatitie (FAP) peaks were detected in the BG5, BG10, and BG20 groups. There was no significant difference in the shear bond strength among all experimental groups. BAG-incorporated GIC precipitated FAP crystals underlying demineralized dentin surface without affecting bond strength. This study suggests the possibility of BAG as a beneficial additive in GIC.
Mass molecular testing for COVID19 using NGS-based technology and a highly scalable workflow
Authors: de Mello Malta Fernanda , Amgarten Deyvid , Val Felipe Camilo , Cervato Murilo Castro , de Azevedo Bruna Mascaro Cordeiro , de Souza Basqueira Marcela , dos Santos Alves Camila Oliveira , Nobrega Maria Soares , de Souza Reis Rodrigo , Sebe Pedro , Gretschischkin Michel Chieregato , de Oliveira Diego Delgado Colombo , Nakamura Carolina Naomi Izo , Chazanas Pedro Lui Nigro , Pinho João Renato Rebello
Published: March 2021

Since the first reported case of the new coronavirus infection in Wuhan, China, researchers and governments have witnessed an unseen rise in the number of cases. Thanks to the rapid work of Chinese scientists, the pathogen now called SARS-CoV-2 has been identified and its whole genome was deposited in public databases by early January 2020. The availability of the genome has allowed researchers to develop Reverse Transcription—Polymerase Chain Reaction (RT-PCR) assays, which are now the gold-standard for molecular diagnosis of the respiratory syndrome COVID19. Because of the rising number of cases and rapid spreading, the world has been facing a shortage of RT-PCR supplies, especially the ones involved in RNA extraction. This has been a major bottleneck to increase testing capacity in many countries that do not significantly manufacture these supplies, such as Brazil. Additionally, RT-qPCR scalability is highly dependent on equipment that usually performs testing of 96 samples at a time. In this work, we describe a cost-effective molecular NGS-based test for diagnosis of COVID19, which uses a single-step RNA extraction and presents high scalability and accuracy when compared to the gold-standard RT-qPCR. A single run of the NGS-based test using the Illumina NextSeq 550 mid-end sequencing equipment is able to multiplex 1,536 patient’s samples, providing individual semi-qualitative results (detected, not detected). Detected results are provided with fragments per million (FPM) values, which was demonstrated to correlate with RT-qPCR Cycle Threshold (CT) values. Besides, usage of the high-end Illumina Novaseq platform may yield diagnostic for up to 6144 samples in a single run. Performance results when compared with RT-qPCR show general accuracy of 96%, and 98% when only samples with CT values (gene N) lower than 30 are considered. We have also developed an online platform, termed VarsVID, to help test executors to easily scale testing numbers. Sample registering, wet-lab worksheets generation, sample sheet for sequencing and results’ display are all features provided by VarsVID. Altogether, these results will contribute to control COVID19 pandemics.