bluuebunny/crossref_metadata_2025 huggingface dataset:
Nonstationary coherence–incoherence patterns in nonlocally coupled heterogeneous phase oscillators
Authors: Omel’chenko Oleh E.
Published: April 2020

We consider a large ring of nonlocally coupled phase oscillators and show that apart from stationary chimera states, this system also supports nonstationary coherence–incoherence patterns (CIPs). For identical oscillators, these CIPs behave as breathing chimera states and are found in a relatively small parameter region only. It turns out that the stability region of these states enlarges dramatically if a certain amount of spatially uniform heterogeneity (e.g., Lorentzian distribution of natural frequencies) is introduced in the system. In this case, nonstationary CIPs can be studied as stable quasiperiodic solutions of a corresponding mean-field equation, formally describing the infinite system limit. Carrying out direct numerical simulations of the mean-field equation, we find different types of nonstationary CIPs with pulsing and/or alternating chimera-like behavior. Moreover, we reveal a complex bifurcation scenario underlying the transformation of these CIPs into each other. These theoretical predictions are confirmed by numerical simulations of the original coupled oscillator system.
Agglomeration dynamics in liquid–solid particle-laden turbulent channel flows using an energy-based deterministic approach
Authors: Mortimer L. F. , Njobuenwu D. O. , Fairweather M.
Published: April 2020

A deterministic particle–particle agglomeration technique is applied together with direct numerical simulation and four-way coupled Lagrangian particle tracking in order to accurately simulate and investigate fully coupled agglomerating particle-laden channel flows at a shear Reynolds number, Reτ = 180. The collision outcome determination (recoil or aggregate) is based on the balance between kinetic energy dispersed in the collision and the work required to overcome the van der Waals attractive potential. The influence of particle size (dP = 202 μm, 286 μm, and 405 μm), both at a fixed volume fraction (ϕP = 10−3) and a fixed primary injected particle number (NP = 109 313), on the resulting collision and agglomeration dynamics is investigated. Attention is also focused on how collision and agglomeration rates vary throughout the wall-normal regions of the channel flow. The results demonstrate that the normalized collision rates are similar for all particle sizes at the fixed volume fraction but increase with particle size at the fixed particle number, and a preference is observed for collisions to occur close to the walls. Despite this, in all cases considered here, agglomeration events are most frequent at the center of the channel, with agglomeration efficiencies also peaking in this region. In terms of particle diameter effects, the smallest particles exhibit the greatest preference to aggregate, given that a collision has already occurred. Furthermore, whereas normalized collision and agglomeration event counts show differing diameter-dependence based on whether the number of primary particles or the volume fraction is fixed, agglomeration rates show diameter-independence and as such are based solely on particle size and local dispersive properties. Analysis of the dynamic collision properties throughout the channel confirms that agglomeration is favored within the bulk flow region due to low relative particle velocities and small collision angles at this location. The temporal evolution of important interaction properties is investigated, all of which demonstrate stability over the course of the time simulated. Particle diameter is also shown to influence the long-term population of higher-order agglomerates, with (for a given volume fraction) smaller particles aggregating faster to form larger particles. The systems studied, which resemble those present in the processing of nuclear waste, all exhibit substantial agglomeration over the time considered. This reinforces the importance of accurately modeling agglomeration dynamics in flows where electrokinetic interactions are important in order to correctly predict multiphase flow properties over long timeframes.
Properties of grooved Dayem bridge based YBa2Cu3O7−δ superconducting quantum interference devices and magnetometers
Authors: Trabaldo E. , Ruffieux S. , Andersson E. , Arpaia R. , Montemurro D. , Schneiderman J. F. , Kalaboukhov A. , Winkler D. , Lombardi F. , Bauch T.
Published: April 2020

The transport properties of a YBa2Cu3O7−δ superconducting quantum interference device (SQUID) based on grooved Dayem bridge weak links are studied as a function of temperature: at high temperatures (60 K<T<Tc=89 K), the weak links show properties similar to superconductor–normal conductor–superconductor junctions, while at temperatures below 60 K, the weak links behave like short Dayem bridges. Using these devices, we have fabricated SQUID magnetometers with galvanically coupled in-plane pickup loops: at T = 77 K, magnetic field white noise levels as low as 63 fT/Hz have been achieved.
Amplitude chimera and chimera death induced by external agents in two-layer networks
Authors: Verma Umesh Kumar , Ambika G.
Published: April 2020

We report the emergence of stable amplitude chimeras and chimera death in a two-layer network where one layer has an ensemble of identical nonlinear oscillators interacting directly through local coupling and indirectly through dynamic agents that form the second layer. The nonlocality in the interaction among the dynamic agents in the second layer induces different types of chimera-related dynamical states in the first layer. The amplitude chimeras developed in them are found to be extremely stable, while chimera death states are prevalent for increased coupling strengths. The results presented are for a system of coupled Stuart–Landau oscillators and can, in general, represent systems with short-range interactions coupled to another set of systems with long-range interactions. In this case, by tuning the range of interactions among the oscillators or the coupling strength between two types of systems, we can control the nature of chimera states and the system can also be restored to homogeneous steady states. The dynamic agents interacting nonlocally with long-range interactions can be considered as a dynamic environment or a medium interacting with the system. We indicate how the second layer can act as a reinforcement mechanism on the first layer under various possible interactions for desirable effects.
Effect of alloying Ni inner electrodes on the leakage current degradation of BaTiO3-based multilayer ceramic capacitors
Authors: Suzuki Shoichiro , Yamaguchi Shinichi , Doi Akitaka , Abe Shunsuke , Matsuda Makoto , Nakamura Tomoyuki , Ando Akira , Sano Harunobu
Published: April 2020

High-capacitance multilayer ceramic capacitors (MLCCs) are mostly electronic ceramic components in which Ni inner electrodes and BaTiO3-based dielectrics are laminated alternately. Owing to their usefulness in portable electronic devices such as smartphones, there is an ongoing demand to attain an MLCC with smaller dimensions and improved capacity. We investigated the effect of alloying Ni inner electrodes with various elements on the leakage current degradation of MLCCs. Fe, Cu, Zn, and Sn were chosen and added to Ni and co-fired with BaTiO3, from which Cu and Sn were alloyed with Ni. The leakage current degradation time of MLCCs using the Ni–Cu and Ni–Sn inner electrodes was longer than that of MLCCs using the Ni internal electrodes. In particular, the leakage current degradation of the MLCCs using Ni–Sn inner electrodes was significantly suppressed. This suppression effect increased as the thickness of the BaTiO3-based dielectrics decreased. This method of optimization of the Ni inner-electrode composition could lead to further miniaturization and increased capacity of MLCCs.
Comparison of Sb, As, and P doping in Cd-rich CdTe single crystals: Doping properties, persistent photoconductivity, and long-term stability
Authors: Nagaoka Akira , Nishioka Kensuke , Yoshino Kenji , Katsube Ryoji , Nose Yoshitaro , Masuda Taizo , Scarpulla Michael A.
Published: April 2020

Acceptor doping CdTe with group-V elements is promising for increasing the power conversion efficiency of CdTe photovoltaic devices via an increased hole concentration and open circuit voltage (VOC). In past work, we have investigated doping with As in Cd-rich CdTe single crystals grown using the Cd-solvent traveling heater method we have developed. In this study, we compare the doping parameters and stability of hole concentration in the light and dark for P, As, and Sb dopants in crystals cooled very slowly from the growth temperature to approximate thermal equilibrium. In contrast to older reports of a high acceptor ionization energy for Sb, our temperature dependent Hall effect experiments reveal an acceptor ionization energy slightly above 90 meV for Sb doping in the mid 1016 cm−3 range. Room temperature hole concentrations above 1016 cm−3 are observed for P, As, and Sb with each dopant type exhibiting only small changes in hole concentrations over 2 years' time at room temperature. Crystals doped with P, As, or Sb exhibit increased conductivity after above-gap illumination, which decays over periods of minutes to hours depending on temperature. Analysis of the photoconductivity decay reveals a barrier attributed to hole capture of 190–280 meV for the series P, As, and Sb.
Segregation and activation of Sb implanted in Si by UV nanosecond-laser-anneal-induced non-equilibrium solidification
Authors: Tabata Toshiyuki , Raynal Pierre-Edouard , Huet Karim , Everaert Jean-Luc
Published: April 2020

In advanced logic devices, access resistance to transistors is dominated by metal–semiconductor contact resistivity. Recent studies report values below 1 × 10−9 ohm cm2, realizing metastable incorporation of dopants into epitaxially grown semiconductor materials. In this study, we have investigated segregation and activation of antimony (Sb) implanted in silicon (Si) epilayers by using UV nanosecond pulsed laser annealing (LA). The Sb-implanted Si epilayers were partially or fully molten by LA, followed by the analysis of atomic and electrically active dopant concentrations as well as the observation of surface morphology evolution. To discuss the impact of the solute trapping phenomenon on substitutional incorporation of the Sb atoms, we also simulated the evolution of solidification front velocity in the LA-induced non-equilibrium solidification. It is noteworthy that the active level of the Sb atoms largely surpasses their reported equilibrium solubility limit (∼2.6 × 1020 at./cm3 compared to ∼6.8 × 1019 at./cm3) when the non-equilibrium solidification approaches a near-complete solute trapping regime.
A novel liquid-crystal phase is ferroelectric
Authors: Miller Johanna L.
Published: April 2020

Molecular dipoles in a liquid don’t usually spontaneously align. The secret to getting them to do so may be the molecules’ shape.
Barbs of a feather lock together
Authors: Lopatka Alex
Published: April 2020

When a bird extends its wings in flight, microscopic fasteners stick to each other to prevent gaps between the feathers and improve the bird’s macroscopic maneuverability.
Between complacency and panic
Authors: Henderson Gabriel
Published: April 2020

How the rhetoric of moderation has shaped the US government’s approach to risk, from nuclear fear to climate policy.
Association of CAST-gene polymorphism with mRNA levels and meat tenderness in goats
Authors: Rossafa Garcia Odair Scatolin , Simões Araújo Jean Luiz , Gasparino Eliane , Teixeira Rodrigues Marcelo , de Souza Khatlab Angélica , Veiga Rodrigues Paulino Pedro , Chaves da Silva Juliana , Nehme de Azevedo Pedro Cesar , Menck Soares Maria Amélia
Published: April 2020

Context Meat tenderness is affected by numerous factors that can cause considerable economic loss as it is one of the characteristics of meat most appreciated by consumers. Higher expression of the calpastatin gene (CAST) has been associated with a reduced meat tenderness in different animal species. Aims Our main objective of the present study was to evaluate the association of the expression of the CAST gene with the shear force of goat muscle. We also assessed whether variations in gene expression could be explained by the polymorphism already identified by other authors or whether the polymorphism may be associated with phenotypic characteristics such as meat tenderness, slaughter weight and carcass weight. Methods Forty crossbred goats (Saanen × Alpine) were slaughtered at ~150 days of age. So as to obtain the genotype of each animal, blood samples were collected on the day of slaughter for subsequent DNA isolation. On the same day, samples of muscle tissue (Longissimus lumborum) were collected to analyse both gene expression and shear force. Key results Among the seven alleles already known from A to G, the C allele, which is the only one exhibiting exon variation, was not observed in our samples. We found, for the first time, that in goat, the highest CAST-gene expression levels are directly related to an increase in the muscle shear force, as has been described for other species. No statistical difference was observed for shear force, slaughter weight or carcass weight among the different genotypic groups evaluated. However, we observed that the level of expression of the CAST gene within Group 7 (Genotypes GG and GE) presented a higher value that in the other genotypes (P < 0.05), although we did not find a satisfactory explanation for the increase in expression in those genotypes. Conclusions Our results gave support what has already been verified in studies with other species, namely that the calpastatin-gene expression is related to the postmortem meat-tenderising process. Implications The tenderness is an important feature in the choice of meat. Several factors can alter this characteristic, such as breed, age, sex and slaughter weight of animals. The molecular mechanisms involved in ante-morten and postmortem processes are important for improving understanding of how we can identify animals that tend to have softer meat after slaughter by applying new technologies, such as molecular marker.
Cancer epithelia-derived mitochondrial DNA is a targetable initiator of a paracrine signaling loop that confers taxane resistance
Authors: Haldar Subhash , Mishra Rajeev , Billet Sandrine , Thiruvalluvan Manish , Placencio-Hickok Veronica R. , Madhav Anisha , Duong Frank , Angara Bryan , Agarwal Priyanka , Tighiouart Mourad , Posadas Edwin M. , Bhowmick Neil A.
Published: April 2020

Significance

The work provides a conceptual advance in functionally defining the cross talk of tumor epithelia with cancer-associated fibroblastic cells contributing to tumor progression and therapeutic resistance. Independent of protein-based signaling molecules, prostate cancer cells secreted mitochondrial DNA to induce associated fibroblasts to generate anaphylatoxin C3a to support tumor progression in a positive feedback loop. Interestingly, the standard of care chemotherapy, docetaxel, used to treat castrate-resistant prostate cancer was found to further potentiate this paracrine-signaling axis to mediate therapeutic resistance. Blocking anaphylatoxin C3a signaling cooperatively sensitized prostate cancer tumors to docetaxel. We reveal that docetaxel resistance is not a cancer cell-autonomous phenomena and that targeting an immune modulator derived from cancer-associated fibroblasts can limit the expansion of docetaxel-resistant tumors.
Ribosome reactivates transcription by physically pushing RNA polymerase out of transcription arrest
Authors: Stevenson-Jones Flint , Woodgate Jason , Castro-Roa Daniel , Zenkin Nikolay
Published: April 2020

Significance

Transcription and translation are coupled in bacteria, meaning that translation of the nascent mRNA by ribosome happens simultaneously with its synthesis by RNA polymerase (RNAP). Uncoupling of transcription from translation may lead to arrest of transcription via backtracking of RNAP along the template, leading to conflicts with DNA replication, although the molecular mechanisms involved are unclear. We assembled an in vitro coupled transcription–translation system in which both machineries can be controlled with single-nucleotide precision. We showed that through a direct interaction, the coupled ribosome, physically pushes RNAP from the backtracked state, thereby reactivating transcription. This rescue ability of the ribosome prevents inhibition of translation by transcriptional backtracking and mitigates conflicts of backtracked RNAPs with replication at protein-coding genes.
Modernity and Its Discontents: Newspapers, Censorship, and the Press Law in Late Nineteenth and Early Twentieth Century Iran
Authors: Nabavi Negin
Published: April 2020

The ratification of the Press Law in February 1908 marked a significant development in the history of censorship in Iran. However, in the little that has been written on this subject, the Press Law has been explained primarily in terms of constitutional politics, and the pressure that the first majles was put under by royalist forces who had been upset at the critical and anti-royalist tone of constitutional newspapers. This article takes a different approach; it contextualizes the Press Law and evaluates it in light of the attempts at control that had been put into effect by the state in the pre-constitutional years. To this end, this article considers the largely untold story of censorship in Qājār Iran. How did the understanding of what censorship should entail evolve through the years? How was censorship exercised, and what challenges did censorship pose for both the authorities and the subjects in the Nāseri and Mozaffari eras, culminating in the Press Law in February 1908?
Cyclin B1-Cdk1 facilitates MAD1 release from the nuclear pore to ensure a robust spindle checkpoint
Authors: Jackman Mark , Marcozzi Chiara , Barbiero Martina , Pardo Mercedes , Yu Lu , Tyson Adam L. , Choudhary Jyoti S. , Pines Jonathon
Published: April 2020

How the cell rapidly and completely reorganizes its architecture when it divides is a problem that has fascinated researchers for almost 150 yr. We now know that the core regulatory machinery is highly conserved in eukaryotes, but how these multiple protein kinases, protein phosphatases, and ubiquitin ligases are coordinated in space and time to remodel the cell in a matter of minutes remains a major question. Cyclin B1-Cdk is the primary kinase that drives mitotic remodeling; here we show that it is targeted to the nuclear pore complex (NPC) by binding an acidic face of the kinetochore checkpoint protein, MAD1, where it coordinates NPC disassembly with kinetochore assembly. Localized cyclin B1-Cdk1 is needed for the proper release of MAD1 from the embrace of TPR at the nuclear pore so that it can be recruited to kinetochores before nuclear envelope breakdown to maintain genomic stability.
Grid-type transparent conductive thin films of carbon nanotubes as capacitive touch sensors
Authors: Valasma Ronja , Bozo Eva , Pitkänen Olli , Järvinen Topias , Dombovari Aron , Mohl Melinda , Lorite Gabriela Simone , Kiss Janos , Konya Zoltan , Kordas Krisztian
Published: April 2020

Transparent conductive films are used in a wide variety of devices. While solar cell top electrodes as well as tablet and mobile phone screens require high optical transparency and low sheet resistance (>80% and <10 Ω/□) to maximize power efficiency; other, less demanding applications, such as those in capacitive touch panels and antistatic coatings, in which only small currents are involved, can be managed with coatings of moderate conductivity. In this paper, we show that area-selective argon plasma treated polyethylene terephthalate surfaces are suitable for localized deposition of carbon nanotubes from their aqueous dispersions by a simple dip coating and subsequent drying processes. The as-deposited carbon nanotubes form entangled networks in microscopic patterns over the plasma-treated surface areas with sheet resistance of <1 kΩ/□ and optical transparency of ~75%. Based on this process, we demonstrate grid-type transparent conductive thin films of carbon nanotubes as capacitive touch sensors. Since each process step is robust, easy to up and downscale, and may be implemented even in roll-to-roll and sheet-to-sheet fabrication, the demonstrated technology is promising to produce grid-type structures even at an industrial scale in the future.
Self-ordering and cavity cooling using a train of ultrashort pulses
Authors: Torggler Valentin , Krešić Ivor , Ban Ticijana , Ritsch Helmut
Published: April 2020

A dilute atomic gas in an optical resonator exhibits a phase transition from a homogeneous density to crystalline order when laser illuminated orthogonal to the resonator axis. We study this well-known self-organization phenomenon for a generalized pumping scheme using a femtosecond pulse train with a frequency spectrum spanning a large bandwidth covering many cavity modes. We show that due to simultaneous scattering into adjacent longitudinal cavity modes the induced light forces and the atomic dynamics becomes nearly translation-invariant along the cavity axis. In addition the laser bandwidth introduces a new correlation length scale within which clustering of the atoms is energetically favorable. Numerical simulations allow us to determine the self-consistent ordering threshold power as function of bandwidth and atomic cloud size. We find strong evidence for a change from a second order to a first order self-ordering phase transition with growing laser bandwidth when the size of the atomic cloud gets bigger than the clustering length. An analysis of the cavity output reveals a corresponding transition from a single to a double pulse traveling within the cavity. This doubles the output pulse repetition rate and creates extra substructures in close analogy to a time crystal formation in the cavity output. Simulations also show that multi-mode operation significantly improves cavity cooling generating lower kinetic temperatures at a much faster cooling rate.
Thermal ions heat transport induced by reversed shear Alfvén eigenmode on the HL-2A tokamak
Authors: Shi P.W. , Qiu Z.Y. , Chen W. , Wang Z.X. , Shi Z.B. , Yu L.M. , Yang Z.C. , Zhong W.L. , Jiang M. , Ji X.Q. , Yang Q.W. , Xu M. , Duan X.R.
Published: April 2020

Experimental investigations of thermal ions heat transport induced by reversed shear Alfvén eigenmodes (RSAEs) have been carried out on the HL-2A tokamak. It is found that the RSAEs are driven unstable by passing particles during the second half of sawtooth periods, and can not only degrade the bremsstrahlung radiations, but also cause obvious reduction of the ion temperature in the core plasma. Interestingly, the RSAEs excited by energetic ions can resonant with the thermal ions, and then lead to a heat transport process. Statistical results suggest there is a quadratic dependence between thermal ion heat flux perturbation and mode amplitude, which indicates a diffusive mechanism of plasma transport and is well explained by the theoretical interpretations derived from quasi-linear transport theory.
Effectiveness and safety of mandatory antimicrobial indications and durations and a pharmacist-driven 48-hour time-out in a pediatric hospital
Authors: Wirtz Ann L , Burns Alaina N , Lee Brian R , Frank Tammy S , Fitzmaurice Laura , Ogden Richard K , O’Neal Brian C , Goldman Jennifer L
Published: April 2020

Purpose

To evaluate the effectiveness and safety of mandatory antimicrobial indications and durations (MAID) and a pharmacist-driven 48-hour time-out in a pediatric hospital.

Methods

MAID and a 48-hour time-out were implemented on February 14, 2017. Antibiotic days of therapy (DOT) per 1,000 patient days were compared between the pre- and postperiod for select antibiotics using unadjusted Poisson models. A prepost comparison was used to compare antimicrobial stewardship program (ASP) intervention rates between time periods. A 2-step process, including distribution of a discontinuation (DC) report to pharmacists and ASP-prompted reorders, was instituted to reduce unintentional antimicrobial discontinuation with MAID. ASP-prompted reorders occurred only when a discrepancy persisted between the order and provider-desired duration. Missed antimicrobial doses were identified by ASP and the institutional event reporting system. Safety of MAID was assessed by reviewing the rate and details of ASP-prompted reorders and missed antimicrobial doses.

Results

A significant decrease in DOT per 1,000 patient days was observed for cefazolin (39.7 to 36.9; P < 0.001), ampicillin (39.9 to 35.7; P < 0.001), clindamycin (38.2 to 35.9; P < 0.001), ceftriaxone (46.5 to 43.4; P < 0.001), and meropenem (8.7 to 6.6; P < 0.001) following implementation. No change in ASP intervention rate occurred between the pre- and postperiod (16.9 vs 16.8%; P = 0.94). With MAID, ASP-prompted reorder occurred on 7.3% of orders. Unintentional discontinuations resulting in missed antimicrobial doses occurred in 3 orders (0.07%); no patient harm resulted.

Conclusion

MAID and a 48-hour time-out significantly reduced DOT of select antibiotics. No patient harm occurred with the 2-step safety process.
Insights into phylogeny, age and evolution of Allium (Amaryllidaceae) based on the whole plastome sequences
Authors: Xie Deng-Feng , Tan Jin-Bo , Yu Yan , Gui Lin-Jian , Su Dan-Mei , Zhou Song-Dong , He Xing-Jin
Published: April 2020

Background and Aims

The genus Allium L., one of the largest monocotyledonous genera and one that includes many economically important crops with nutritional and medicinal value, has been the focus of classification or phylogeny studies for centuries. Recent studies suggested that the genus can be divided into 15 subgenera and 72 sections, which were further classified into three evolutionary lineages. However, the phylogenetic relationships reconstructed by one or two loci showed weaker support, especially for the third evolutionary lineage, which might not show the species relationships very clearly and could hinder further adaptive and evolutionary study.

Methods

In this study, a total of 39 complete chloroplast genomes of Allium (covering 12 Allium subgenera) were collected, and combining these with 125 species of plastomes from 19 other families of monocots, we reconstructed the phylogeny of the genus Allium, estimated the origin and divergence time of the three evolutionary lineages and investigated the adaptive evolution in this genus and related families.

Results

Our phylogenetic analysis confirmed the monophyly and three evolutionary lineages of Allium, while new species relationships were detected within the third evolutionary lineage. The divergence time of the three evolutionary lineages was estimated to be in the early Eocene to the middle Miocene, and numerous positive selected genes (PSGs) and PSGs with high average Ka/Ks values were found in Allium species.

Conclusions

Our results detected a well-supported phylogenetic relationship of Allium. The PSGs and PSGs with high Ka/Ks values, as well as diversified morphologies, complicated chromosome characteristics and unique reproductive modes may play important roles in the adaptation and evolution of Allium species. This is the first study that conducted phylogenetic and evolutionary analyses on the genus Allium combined with the plastome and morphological and cytological data. We hope that this study can contribute to further analysis of Allium for other researchers.
The Impact of Self-Efficacy and Health Locus of Control on Performance Validity Testing
Authors: Armistead-Jehle Patrick , Lippa Sara M , Grills Chad E
Published: April 2020

Objective

Recent research has examined potential influences to performance validity testing beyond intentional feigning. The current study sought to examine the hypothesized relationships of two psychological constructs (self-efficacy and health locus of control) with performance validity testing (PVT).

Method

Retrospective review of 158 mild traumatic brain injury (mTBI) cases referred to an Army outpatient clinic for neuropsychological evaluation. The mTBI cases were classified according to passing or failing the Medical Symptom Validity Test (MSVT) or Non-Verbal Medical Symptom Validity Test (NV-MSVT). Group comparisons were performed utilizing one-way ANOVA to evaluate the differences between the PVT-Pass and PVT-Fail groups on self-efficacy (MMPI-2-RF Inefficacy scale) and locus of control (Multi-Dimensional Health Locus of Control).

Results

There was no relationship between self-efficacy or health locus of control and passing/failing PVTs.

Conclusions

Further research is warranted to explore potential influences on PVT performance, which we conceptualize as analogous to experimental nuisance variables that may be amenable to intervention.
Phylogenetics and population structure of the steppe speciesHycleus polymorphus(Coleoptera: Meloidae: Mylabrini) reveal multiple refugia in Mediterranean mountain ranges
Authors: Riccieri Alessandra , Mancini Emiliano , Iannella Mattia , Salvi Daniele , Bologna Marco A
Published: April 2020

Many continental species distributed in the Eurasian steppe occur as relict populations in the mountains of Western Europe. Their biogeographical responses to Quaternary climate changes have been poorly studied; however, they could have responded as cold-adapted species. We investigated the biogeographic history of a steppe beetle, Hycleus polymorphus, using mitochondrial and nuclear DNA sequences (COI, CAD, ITS2), and species distribution modelling (SDM) under present and past bioclimatic envelopes. We first performed a phylogenetic assessment to define species boundaries within the H. polymorphus species group. Specimens previously treated as Hycleus humerosus on morphological grounds are assigned to H. polymorphus, and those identified as Hycleus zebraeus assigned to Hycleus atratus. ITS2 data analyses revealed a strong phylogeographical structure of H. polymorphus populations, with four haplogroups corresponding to the (i) Italian Alps, (ii) French Alps and Pyrenees, (iii) South Balkan and Pontic mountains, and (iv) North Dinaric Alps. Based on these analyses and the SDM, we propose that during a glacial period, following the spread of steppic habitat, H. polymorphus underwent a range expansion from Asia to South-West Europe. Within the Mediterranean area, during the last interglacial the climatic suitability for the species was limited to mountains that acted as refugia and prompted allopatric divergence into four main lineages.
Occurrence of crassulacean acid metabolism in Colombian orchids determined by leaf carbon isotope ratios
Authors: Torres-Morales Germán , Lasso Eloisa , Silvera Katia , Turner Benjamin L , Winter Klaus
Published: April 2020

Many Orchidaceae, especially those occupying periodically dry, epiphytic microhabitats in the humid tropics, are believed to engage in the water-conserving crassulacean acid metabolism (CAM) photosynthetic pathway. However, the photosynthetic pathway has been studied in only c. 5% of all orchid species. Here we extend the survey to 1079 orchid species, mainly from Colombia, by assessing the presence of CAM based on the carbon isotopic signature (δ 13C values) of herbarium specimens. Ninety-six species, representing 8.9% of those analysed, had δ 13C values less negative than −20‰, indicating CAM. Epiphytism was the predominant life form (75.2% of species sampled), and 9.4% of these epiphytes showed a CAM-type isotopic signature. Isotope values suggested CAM in 19 terrestrial orchid species, 14 species from high elevation (2000–3400 m) and species from six genera that were previously unknown to engage in CAM (Jacquiniella, Meiracyllium, Pabstiella, Psychopsis, Pterostemma and Solenidium). We conclude that CAM is the major pathway of carbon acquisition in a small but broadly distributed fraction of tropical orchids and is more prevalent at lower elevations.
Early Insights From Clinical Trials of Typhoid Conjugate Vaccine
Authors: Neuzil Kathleen M , Basnyat Buddha , Clemens John D , Gordon Melita A , Patel Priyanka D , Pollard Andrew J , Shakya Mila , Qadri Firdausi
Published: April 2020

Clinical trials of typhoid conjugate vaccine (TCV) are ongoing in 4 countries. Early data confirm safety, tolerability, and immunogenicity of typhoid conjugate vaccine, and early efficacy results are promising. These data support World Health Organization recommendations and planned country introductions. Forthcoming trial data will continue to inform programmatic use of typhoid conjugate vaccine.
SARS-CoV-2 Is Not Detectable in the Vaginal Fluid of Women With Severe COVID-19 Infection
Authors: Qiu Lin , Liu Xia , Xiao Meng , Xie Jing , Cao Wei , Liu Zhengyin , Morse Abraham , Xie Yuhua , Li Taisheng , Zhu Lan
Published: April 2020

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is spread mainly through respiratory droplets or direct contact. However, the infection condition of the genital system is unknown. Our aim in this study was to determine if SARS-CoV-2 is present in the vaginal fluid of women with coronavirus disease 2019 (COVID-19).

Methods

Ten women with confirmed severe COVID-19 pneumonia admitted to the Tongji Zhongfa Hospital intensive care unit from 4 February 2020 through 24 February 2020 were included. Clinical records, laboratory results, and computed tomography examinations were retrospectively reviewed. The potential for genital infection was accessed by testing for the presence of SARS-CoV-2 in vaginal fluids obtained from vaginal swab samples. Reverse transcriptase polymerase chain reaction was used to confirm the SARS-CoV-2 infection in vaginal fluids.

Results

The clinical characteristics of the 10 women were similar to those reported in other severe COVID-19 patients. All 10 patients were tested for SARS-CoV-2 in vaginal fluid, and all samples tested negative for the virus.

Conclusions

Findings from this small group of cases suggest that SARS-CoV-2 virus does not exist in the vaginal fluids of severe COVID-19 patients.
Zinc ameliorates human aortic valve calcification through GPR39 mediated ERK1/2 signalling pathway
Authors: Chen Ziying , Gordillo-Martinez Flora , Jiang Lei , He Pengcheng , Hong Wanzi , Wei Xuebiao , Staines Katherine A , Macrae Vicky E , Zhang Chunxiang , Yu Danqing , Fu Xiaodong , Zhu Dongxing
Published: April 2020

Aims

Calcific aortic valve disease (CAVD) is the most common heart valve disease in the Western world. It has been reported that zinc is accumulated in calcified human aortic valves. However, whether zinc directly regulates CAVD is yet to be elucidated. The present study sought to determine the potential role of zinc in the pathogenesis of CAVD.

Methods and results

Using a combination of a human valve interstitial cell (hVIC) calcification model, human aortic valve tissues, and blood samples, we report that 20 μM zinc supplementation attenuates hVIC in vitro calcification, and that this is mediated through inhibition of apoptosis and osteogenic differentiation via the zinc-sensing receptor GPR39-dependent ERK1/2 signalling pathway. Furthermore, we report that GPR39 protein expression is dramatically reduced in calcified human aortic valves, and there is a significant reduction in zinc serum levels in patients with CAVD. Moreover, we reveal that 20 μM zinc treatment prevents the reduction of GPR39 observed in calcified hVICs. We also show that the zinc transporter ZIP13 and ZIP14 are significantly increased in hVICs in response to zinc treatment. Knockdown of ZIP13 or ZIP14 significantly inhibited hVIC in vitro calcification and osteogenic differentiation.

Conclusions

Together, these findings suggest that zinc is a novel inhibitor of CAVD, and report that zinc transporter ZIP13 and ZIP14 are important regulators of hVIC in vitro calcification and osteogenic differentiation. Zinc supplementation may offer a potential therapeutic strategy for CAVD.
The role of angiotensin-converting enzyme 2 in coronaviruses/influenza viruses and cardiovascular disease
Authors: Chen Li , Hao Guang
Published: April 2020

Angiotensin-converting enzyme 2 (ACE2) has emerged as a key regulator of the renin–angiotensin system in cardiovascular (CV) disease and plays a pivotal role in infections by coronaviruses and influenza viruses. The present review is primarily focused on the findings to indicate the role of ACE2 in the relationship of coronaviruses and influenza viruses to CV disease. It is postulated that the risk of coronavirus or influenza virus infection is high, at least partly due to high ACE2 expression in populations with a high CV risk. Coronavirus and influenza virus vaccine usage in high CV risk populations could be a potential strategy to prevent both CV disease and coronavirus/influenza virus infections.
Measuring the Indirect Effects of Adverse Employer Behaviour on Worker Productivity: a field Experiment
Authors: Heinz Matthias , Jeworrek Sabrina , Mertins Vanessa , Schumacher Heiner , Sutter Matthias
Published: April 2020

We conduct a field experiment to study how worker productivity is affected if employers act adversely towards their co-workers. Our employees work for two shifts in a call centre. In our main treatment, we lay off some workers before the second shift. Compared to two control treatments, we find that the lay-off reduces the productivity of unaffected workers by 12%. We find suggestive evidence that this result is not driven by altered beliefs about the job or the management’s competence, but caused by the workers’ perception of unfair employer behaviour. The latter interpretation is confirmed in a prediction experiment with professional HR managers. Our results suggest that the price for adverse employer behaviour goes well beyond the potential tit for tat of directly affected workers.
Uniportal video-assisted thoracoscopic carinal resections: technical aspects and outcomes
Authors: Sekhniaidze Dmitrii , Gonzalez-Rivas Diego , Kononets Pavel , Garcia Alejandro , Shneider Vladimir , Agasiev Malik , Ganzhara Ivan
Published: April 2020

OBJECTIVES

Important benefits in uniportal video-assisted thoracoscopic surgery (VATS) for lung cancer have recently been achieved. However, the use of this technique for complex sleeve procedures is limited. We describe the technical aspects of and patient outcomes following carinal resections using uniportal VATS.

METHODS

Since 2015, 16 sleeve carinal resections, including 11 right pneumonectomies, 4 right upper lobectomies and 1 lung-sparing carinal resection, have been performed at the Regional Clinic Hospital, Tyumen, Russia.

RESULTS

The mean surgical time was 215.9 ± 67.2 min (range 125–340 min). The mean blood loss volume was 256.3 ± 284.5 ml (range 50–1200 ml). There was 1 case of conversion to thoracotomy. The morbidity rate was 25%, and the mortality rate was 0%. The median overall survival was 38.6 ± 3.5 months.

CONCLUSIONS

The use of uniportal VATS for carinal resections in certain patients allows for radical resections with low rates of morbidity and mortality.
Spontaneous ventilation video-assisted thoracoscopic surgery for patients with non-small-cell lung cancer with excess body weight
Authors: Wu Donghong , Liang Hengrui , Liang Wenhua , Liu Hui , Wang Chuqiao , Wen Yaokai , Jiang Yu , Su Zixuan , Peng Haoxin , Wang Runchen , Chen Yingying , Jiang Long , Zhao Yi , Wang Wei , Liu Jun , He Jianxing
Published: April 2020

OBJECTIVES

The feasibility and safety of spontaneous ventilation (SV) video-assisted thoracoscopic surgery (VATS) for non-small-cell lung cancer (NSCLC) in patients with excess body weight [defined as body mass index (BMI) ≥ 25 kg/m2] remain unclear.

METHODS

Patients with NSCLC with excess body weight who underwent SV-VATS or mechanical ventilation (MV) VATS (MV-VATS) between April 2012 and July 2018 were analysed retrospectively. Propensity score matching was applied to balance the distribution of demographic characteristics. The short-term outcomes between the SV-VATS group and MV-VATS group were compared.

RESULTS

From April 2012 to July 2018, a total of 703 patients with excess body weight were included, 68 of whom underwent SV-VATS and 635 of whom underwent MV-VATS. After propensity score matching, the distribution of demographic characteristics was well balanced. BMIs (26.65 ± 1.74 vs 27.18 ± 2.36 kg/m2; P = 0.29) were similar between the groups. Patients who underwent SV-VATS had similar anaesthesia times (213 ± 57 vs 233 ± 67 min; P = 0.16) and similar operative times (122 ± 44 vs 142 ± 56 min; P = 0.086). The intraoperative bleeding volume, postoperative chest tube duration, volume of pleural drainage, number of dissected N1 and N2 station lymph nodes, length of hospitalization and incidence of complications were comparable between the 2 groups.

CONCLUSIONS

Primary lung cancer resection is feasible and not associated with safety issues under SV-VATS in selected patients with NSCLC with excess body weight.
Integration of absolute cardiovascular disease risk assessment into routine blood cholesterol testing at pathology services
Authors: Chapman Niamh , Fonseca Ricardo , Murfett Leigh , Beazley Kevin , McWhirter Rebekah E , Schultz Martin G , Nelson Mark R , Sharman James E
Published: April 2020

Background

Absolute cardiovascular disease (CVD) risk assessment is recommended for primary prevention of CVD, yet uptake in general practice is limited. Cholesterol requests at pathology services provide an opportunity to improve uptake by integrating absolute CVD risk assessment with this service.

Objective

This study aimed to assess the feasibility of such an additional service.

Methods

Two-hundred and ninety-nine patients (45–74 years) referred to pathology services for blood cholesterol had measurement of all variables required to determine absolute CVD risk according to Framingham calculator (blood pressure, age, sex, smoking and diabetes status via self-report). Data were recorded via computer-based application. The absolute risk score was communicated via the report sent to the referring medical practitioner as per usual practice. Evaluation questionnaires were completed immediately post visit and at 1-, 3- and 6-month follow-up via telephone (n = 262).

Results

Absolute CVD risk reports were issued for 90% of patients. Most patients (95%) reported that the length of time for the pathology service assessment was acceptable, and 91% that the self-directed computer-based application was easy to use. Seventy-eight per cent reported a preference for pathology services to conduct absolute CVD risk assessment. Only 2% preferred a medical practitioner. Of follow-up patients, 202 (75%) had a consultation with a medical practitioner, during which, aspects of CVD risk prevention were discussed (cholesterol and blood pressure 74% and 69% of the time, respectively).

Conclusions

Measurement of absolute CVD risk in pathology services is feasible, highly acceptable among middle-to-older adults and may increase uptake of guideline-directed care in general practice.
The O-GlcNAc modification promotes terminal differentiation of human corneal epithelial cells
Authors: McColgan Nicole M , Feeley Marissa N , Woodward Ashley M , Guindolet Damien , Argüeso Pablo
Published: April 2020

Dynamic modification of nuclear and cytoplasmic proteins with O-linked β-N-acetylglucosamine (O-GlcNAc) plays an important role in orchestrating the transcriptional activity of eukaryotic cells. Here, we report that the O-GlcNAc modification contributes to maintaining ocular surface epithelial homeostasis by promoting mucin biosynthesis and barrier function. We found that induction of human corneal epithelial cell differentiation stimulated the global transfer of O-GlcNAc to both nuclear and cytosolic proteins. Inflammatory conditions, on the other hand, were associated with a reduction in the expression of O-GlcNAc transferase at the ocular surface epithelia. Loss- and gain-of-function studies using small interfering RNA targeting O-GlcNAc transferase, or Thiamet G, a selective inhibitor of O-GlcNAc hydrolase, respectively, revealed that the presence of O-GlcNAc was necessary to promote glycocalyx barrier function. Moreover, we found that Thiamet G triggered a correlative increase in both surface expression of MUC16 and apical epithelial cell area while reducing paracellular permeability. Collectively, these results identify intracellular protein O-glycosylation as a novel pathway responsible for promoting the terminal differentiation of human corneal epithelial cells.
The dawn of the future: 30 years from the first biopsy of a human embryo. The detailed history of an ongoing revolution
Authors: Cimadomo Danilo , Rienzi Laura , Capalbo Antonio , Rubio Carmen , Innocenti Federica , García-Pascual Carmen María , Ubaldi Filippo Maria , Handyside Alan
Published: April 2020

Following early studies showing no adverse effects, cleavage stage biopsy by zona drilling using acid Tyrode’s solution, and removal of single blastomeres for preimplantation genetic testing (PGT) and identification of sex in couples at risk of X-linked disease, was performed by Handyside and colleagues in late 1989, and pregnancies reported in 1990. This method was later used for specific diagnosis of monogenic conditions, and a few years later also for chromosomal structural and/or numerical impairments, thereby establishing a valuable alternative option to prenatal diagnosis. This revolutionary approach in clinical embryology spread worldwide, and several other embryo biopsy strategies developed over three decades in a process that is still ongoing. The rationale of this narrative review is to outline the different biopsy approaches implemented across the years in the workflow of the IVF clinics that provided PGT: their establishment, the first clinical experiences, their downsides, evolution, improvement and standardization. The history ends with a glimpse of the future: minimally/non-invasive PGT and experimental embryo micromanipulation protocols. This grand theme review outlines a timeline of the evolution of embryo biopsy protocols, whose implementation is increasing worldwide together with the increasing application of PGT techniques in IVF. It represents a vade mecum especially for the past, present and upcoming operators and experts in this field to (re)live this history from its dawn to its most likely future.