bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coordinate regulation of the expression of SdsR toxin and its downstream pphA gene by RyeA antitoxin in Escherichia coli
Authors: Choi Jee Soo , Park Hongmarn , Kim Wonkyong , Lee Younghoon 
Published: July 2019

AbstractIn Escherichia coli, SdsR and RyeA, a unique pair of mutually cis-encoded small RNAs (sRNAs), act as toxin and antitoxin, respectively. SdsR and RyeA expression are reciprocally regulated; however, how each regulates the synthesis of the other remains unclear. Here, we characterized the biosynthesis of the two sRNAs during growth and investigated their coordinate regulation using sdsR and ryeA promoter mutant strains. We found that RyeA transcription occurred even upon entry of cells into the stationary phase, but its apparent expression was restricted to exponentially growing cells because of its degradation by SdsR. Likewise, the appearance of SdsR was delayed owing to its RyeA-mediated degradation. We also found that the sdsR promoter was primarily responsible for transcription of the downstream pphA gene encoding a phosphatase and that pphA mRNA was synthesized by transcriptional read-through over the sdsR terminator. Transcription from the σ70-dependent ryeA promoter inhibited transcription from the σS-dependent sdsR promoter through transcriptional interference. This transcriptional inhibition also downregulated pphA expression, but RyeA itself did not downregulate pphA expression.
Tunable vector-vortex beam optical parametric oscillator
Authors: Sharma Varun , Kumar S. Chaitanya , Aadhi A. , Ye H. , Samanta G. K. , Ebrahim-Zadeh M. 
Published: July 2019

AbstractVector-vortex beams, having both phase and polarization singularities, are of great interest for a variety of applications. Generally, such beams are produced through systematic control of phase and polarization of the laser beam, typically external to the source. However, efforts have been made to generate vector-vortex beams directly from the laser source. Given the operation of the laser at discrete wavelengths, vector-vortices are generated with limited or no wavelength tunability. Here, we report an experimental scheme for the direct generation of vector-vortex beams. Exploiting the orbital angular momentum conservation and the broad wavelength versatility of an optical parametric oscillator, we systematically control the polarization of the resonant beam using a pair of intracavity quarter-wave plates to generate coherent vector-vortex beam tunable across 964–990 nm, with output states represented on the higher-order Poincaré sphere. The generic experimental scheme paves the way for new sources of structured beams in any wavelength range across the optical spectrum and in all time-scales from continuous-wave to ultrafast regime.
Dysfunctional MDR-1 disrupts mitochondrial homeostasis in the oocyte and ovary
Authors: Clark Haley , Knapik Laura O. , Zhang Zijing , Wu Xiaotian , Naik Mandar T. , Oulhen Nathalie , Wessel Gary M. , Brayboy Lynae M. 
Published: July 2019

AbstractMultidrug resistance transporters (MDRs) are best known for their pathological role in neoplastic evasion of chemotherapeutics and antibiotics. Here we show that MDR-1 is present in the oocyte mitochondrial membrane, and it protects the female gamete from oxidative stress. Female mdr1a mutant mice have no significant difference in ovarian follicular counts and stages, nor in reproductively functioning hormone levels, yet these mice are significantly more vulnerable to gonadotoxic chemotherapy, have chronically elevated reactive oxygen species in immature germinal vesicle oocytes, exhibit a significant over-accumulation of metabolites involved in the tricarboxylic acid cycle (TCA), and have abnormal mitochondrial membrane potential. The mdr1a mutant ovaries have a dramatically different transcriptomic profile with upregulation of genes involved in metabolism. Our findings indicate that functionality of MDR-1 reveals a critical intersection of metabolite regulation, oxidative stress, and mitochondrial dysfunction that has direct implications for human infertility, premature reproductive aging due to oxidative stress, and gonadoprotection.
Microscopic model for radiation-induced magnetoresistance oscillations excited by circularly polarized radiation
Authors: Iñarrea Jesús 
Published: July 2019

AbstractWe develop a microscopic model to explain the striking result of immunity to the sense of circularly polarized radiation of the photo-excited resistance oscillations in high-mobility 2D electron systems. Our model is based on the radiation-driven electron orbit model, previously developed to explain the photo-induced resistance oscillations and zero resistance states in these systems. According to it, the guiding center of the Landau states when irradiated by circularly polarized radiation performs a circular path driven by radiation. In principle, in an infinite sample, this path is different according to the the sense of circular polarization (left or right). However, the limited size of the sample with the essential role of the edges and the concurrent presence of the Hall electric field tend to quench the displacement of the driven guiding center making nearly equal both trajectories. In the end and in the presence of scattering, the longitudinal irradiated magnetoresistance turns out nearly the same irrespective of the sense of circular radiation.
Particle morphomics by high-throughput dynamic image analysis
Authors: Sun Youmin , Cai Zhengqing , Fu Jie 
Published: July 2019

AbstractA novel omics-like method referred to as “particle morphomics” has been proposed in the present study. The dynamic images of >2,000,000 particles per sample in sediments, soils and dusts were collected by a Sympatec GmbH QICPIC particle size and shape analyzer, and the morphological descriptors of each particle including equivalent diameter, sphericity, aspect ratio and convexity were extracted as the “particle morphome”. Various multivariate analyses were adopted to process the high-throughput data of particle morphome including analyses of alpha and beta diversities, similarity, correlation, network, redundancy, discretion and principal coordinate. The outcome of particle morphomics could estimate the morphological diversity and sketch the profile of morphological structure, which aided to develop a morphological fingerprint for specific particle samples. The distribution and properties of particle assemblages of specific morphology could also be evaluated by selecting particles with respect to filter criteria. More importantly, the particle morphomics may be extended to investigate and explain the biogeochemical and environmental processes involved with particle morphology if linked with external variables.
Revising of the Purcell effect in periodic metal-dielectric structures: the role of absorption
Authors: Morozov Konstantin M. , Ivanov Konstantin A. , de Sa Pereira Daniel , Menelaou Christopher , Monkman Andrew P. , Pozina Galia , Kaliteevski Mikhail A. 
Published: July 2019

AbstractPeriodic metal-dielectric structures attract substantial interest since it was previously proposed that the spontaneous emission amplification rates (the Purcell factor) in such structures can reach enormous values up to 105. However, the role of absorption in real metals has not been thoroughly considered. We provide a theoretical analysis showing that absorption leads to diminishing values of Purcell factor. We also suggest that using emitting organic compounds such as CBP (4,4-Bis(N-carbazolyl)-1,1-biphenyl) can lead to a moderate increase of about an order of magnitude in the Purcell factor. Defining the experimentally measured Purcell factor as a ratio between the excited state lifetimes in bare CBP and in periodic structure, this increase in the fabricated periodic structure is demonstrated through a 4–8 times decrease in excited state radiative lifetime compared to a bare organic material in a wide emission spectrum.
Macrophages promote a profibrotic phenotype in orbital fibroblasts through increased hyaluronic acid production and cell contractility
Authors: Yang I-Hui , Rose Geoffrey E. , Ezra Daniel G. , Bailly Maryse 
Published: July 2019

AbstractGraves’ orbitopathy (GO) is an autoimmune inflammatory disease affecting the orbit. Orbital fibroblasts are a key component in GO pathogenesis, which includes inflammation, adipogenesis, hyaluronic acid (HA) secretion, and fibrosis. Macrophages are thought to participate in the immunological stage of GO, but whether they can directly affect the fibroblasts phenotype and modulate disease progression is unknown. We previously showed that GO adipogenic and fibrotic phenotypes could be modelled in a pseudo-physiological 3D environment in vitro. Here, we introduced macrophages in this 3D culture model to investigate role for macrophages in modulating adipogenesis, HA production, and contractility in orbital fibroblasts. Macrophages had a minimal effect on lipid droplet formation in fibroblasts, but significantly increased HA production and cell contractility, suggesting that they may promote the fibrotic phenotype. This effect was found to be mediated at least in part through phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) activation and linked to an increase in actin polymerization and protrusive activity in fibroblasts. Overall our work shows for the first time a direct role for macrophages in modulating the fibroblasts’ phenotype in GO, supporting a role for macrophages in the progression of the fibrotic phenotype through induction of HA production and stimulation of the contractile phenotype in orbital fibroblasts.
Screening a library of approved drugs reveals that prednisolone synergizes with pitavastatin to induce ovarian cancer cell death
Authors: Abdullah Marwan Ibrahim , Abed Mohammed Najim , Khanim Farhat , Richardson Alan 
Published: July 2019

AbstractThe survival rate for patients with ovarian cancer has changed little in the past three decades since the introduction of platinum-based chemotherapy and new drugs are needed. Statins are drugs used for the treatment and prevention of cardiovascular diseases. Recent work from our laboratory has shown that pitavastatin has potential as a treatment for ovarian cancer if dietary geranylgeraniol is controlled. However, relatively high doses of statins are required to induce apoptosis in cancer cells, increasing the risk of myopathy, the most common adverse effect associated with statins. This makes it desirable to identify drugs which reduce the dose of pitavastatin necessary to treat cancer. A drug-repositioning strategy was employed to identify suitable candidates. Screening a custom library of 100 off-patent drugs for synergistic activity with pitavastatin identified prednisolone as the most prominent hit. Prednisolone potentiated the activity of pitavastatin in several assays measuring the growth, survival or apoptosis in several ovarian cancer cells lines. Prednisolone, alone or in some cases in combination with pitavastatin, reduced the expression of genes encoding enzymes in the mevalonate pathway, providing a mechanistic explanation for the synergy.
Abnormalities in hubs location and nodes centrality predict cognitive slowing and increased performance variability in first-episode schizophrenia patients
Authors: Krukow Paweł , Jonak Kamil , Karpiński Robert , Karakuła-Juchnowicz Hanna 
Published: July 2019

AbstractIntroducing the Minimum Spanning Tree (MST) algorithms to neural networks science eliminated the problem of arbitrary setting of the threshold for connectivity strength. Despite these advantages, MST has been rarely used to study network abnormalities in schizophrenia. An MST graph mapping a network structure is its simplification, therefore, it is important to verify whether the reconfigured network is significantly related to the behavioural dimensions of the clinical picture of schizophrenia. 35 first-episode schizophrenia patients and 35 matched healthy controls underwent an assessment of information processing speed, cognitive inter-trial variability modelled with ex-Gaussian distributional analysis of reaction times and resting-state EEG recordings to obtain frequency-specific functional connectivity matrices from which MST graphs were computed. The patients’ network had a more random structure and star-like arrangement with overloaded hubs positioned more posteriorly than it was in the case of the control group. Deficient processing speed in the group of patients was predicted by increased maximal betweenness centrality in beta and gamma bands, while decreased consistency in cognitive processing was predicted by the betweenness centrality of posterior nodes in the gamma band, together with duration of illness. The betweenness centrality of posterior nodes in the gamma band was also significantly correlated with positive psychotic symptoms in the clinical group.
Unraveling the effects of the gut microbiota composition and function on horse endurance physiology
Authors: Plancade Sandra , Clark Allison , Philippe Catherine , Helbling Jean-Christophe , Moisan Marie-Pierre , Esquerré Diane , Le Moyec Laurence , Robert Céline , Barrey Eric , Mach Núria 
Published: July 2019

AbstractAn integrated analysis of gut microbiota, blood biochemical and metabolome in 52 endurance horses was performed. Clustering by gut microbiota revealed the existence of two communities mainly driven by diet as host properties showed little effect. Community 1 presented lower richness and diversity, but higher dominance and rarity of species, including some pathobionts. Moreover, its microbiota composition was tightly linked to host blood metabolites related to lipid metabolism and glycolysis at basal time. Despite the lower fiber intake, community type 1 appeared more specialized to produce acetate as a mean of maintaining the energy supply as glucose concentrations fell during the race. On the other hand, community type 2 showed an enrichment of fibrolytic and cellulolytic bacteria as well as anaerobic fungi, coupled to a higher production of propionate and butyrate. The higher butyrate proportion in community 2 was not associated with protective effects on telomere lengths but could have ameliorated mucosal inflammation and oxidative status. The gut microbiota was neither associated with the blood biochemical markers nor metabolome during the endurance race, and did not provide a biomarker for race ranking or risk of failure to finish the race.
On the Triggering Mechanisms of Upward Lightning
Authors: Schumann Carina , Saba Marcelo M. F. , Warner Tom A. , Ferro Marco A. S. , Helsdon John H. , Thomas Ron , Orville Richard E. 
Published: July 2019

AbstractUpward lightning studies took place in Rapid City, South Dakota, USA and S. Paulo, Brazil during the summer thunderstorm seasons from 2011 to 2016. One of the main objectives of these campaigns was to evaluate and characterize the triggering of upward positive leaders from tall objects due to preceding nearby flash activity. 110 upward flashes were observed with a combination of high- and standard-speed video and digital still cameras, electric field meters, fast electric-field antenna systems, and for two seasons, a Lightning Mapping Array. These data were analyzed, along with correlated lightning location system data, to determine the triggering flash type responsible for the initiation of upward leaders from towers. In this paper, we describe the various processes during flash activity that can trigger upward leaders from tall objects in the USA and in Brazil. We conclude that the most effective triggering component is the propagation of the in-cloud negative leader during the continuing current that follows a positive return stroke.
Cryo EM structure of the rabies virus ribonucleoprotein complex
Authors: Riedel Christiane , Vasishtan Daven , Pražák Vojtěch , Ghanem Alexander , Conzelmann Karl-Klaus , Rümenapf Till 
Published: July 2019

AbstractRabies virus is an important zoonotic pathogen. Its bullet shaped particle contains a helical nucleocapsid. We used cryo-electron tomography and subsequent subtomogram averaging to determine the structure of its ribonucleoprotein. The resulting electron density map allowed for confident fitting of the N-protein crystal structure, indicating that interactions between neighbouring N-proteins are only mediated by N- and C-terminal protruding subdomains (aa 1–27 and aa 355–372). Additional connecting densities, likely stabilizing the ribonucleoprotein complex, are present between neighbouring M-protein densities on the same helical turn and between M- and N-protein densities located on neighbouring helical turns, but not between M-proteins of different turns, as is observed for the related Vesicular stomatitis virus (VSV). This insight into the architecture of the rabies virus nucleocapsid highlights the surprising structural divergence of large biological assemblies even if the building blocks – here exemplified by VSV M- and N-protein – are structurally closely related.
Species-Specific Biodegradation of Sporopollenin-Based Microcapsules
Authors: Fan Teng-Fei , Potroz Michael G. , Tan Ee-Lin , Ibrahim Mohammed Shahrudin , Miyako Eijiro , Cho Nam-Joon 
Published: July 2019

AbstractSporoderms, the outer layers of plant spores and pollen grains, are some of the most robust biomaterials in nature. In order to evaluate the potential of sporoderms in biomedical applications, we studied the biodegradation in simulated gastrointestinal fluid of sporoderm microcapsules (SDMCs) derived from four different plant species: lycopodium (Lycopodium clavatum L.), camellia (Camellia sinensis L.), cattail (Typha angustifolia L.), and dandelion (Taraxacum officinale L.). Dynamic image particle analysis (DIPA) and field-emission scanning electron microscopy (FE-SEM) were used to investigate the morphological characteristics of the capsules, and Fourier-transform infrared (FTIR) spectroscopy was used to evaluate their chemical properties. We found that SDMCs undergo bulk degradation in a species-dependent manner, with camellia SDMCs undergoing the most extensive degradation, and dandelion and lycopodium SDMCs being the most robust.
Deep learning-based selection of human sperm with high DNA integrity
Authors: McCallum Christopher , Riordon Jason , Wang Yihe , Kong Tian , You Jae Bem , Sanner Scott , Lagunov Alexander , Hannam Thomas G. , Jarvi Keith , Sinton David 
Published: July 2019

AbstractDespite the importance of sperm DNA to human reproduction, currently no method exists to assess individual sperm DNA quality prior to clinical selection. Traditionally, skilled clinicians select sperm based on a variety of morphological and motility criteria, but without direct knowledge of their DNA cargo. Here, we show how a deep convolutional neural network can be trained on a collection of ~1000 sperm cells of known DNA quality, to predict DNA quality from brightfield images alone. Our results demonstrate moderate correlation (bivariate correlation ~0.43) between a sperm cell image and DNA quality and the ability to identify higher DNA integrity cells relative to the median. This deep learning selection process is directly compatible with current, manual microscopy-based sperm selection and could assist clinicians, by providing rapid DNA quality predictions (under 10 ms per cell) and sperm selection within the 86th percentile from a given sample.
Alcohol sedation in adult Drosophila is regulated by Cysteine proteinase-1 in cortex glia
Authors: Lee Kristen M. , Mathies Laura D. , Grotewiel Mike 
Published: July 2019

AbstractAlthough numerous studies have demonstrated that neuronal mechanisms regulate alcohol-related behaviors, very few have investigated the direct role of glia in behavioral responses to alcohol. The results described here begin to fill this gap in the alcohol behavior and gliobiology fields. Since Drosophila exhibit conserved behavioral responses to alcohol and their CNS glia are similar to mammalian CNS glia, we used Drosophila to begin exploring the role of glia in alcohol behavior. We found that knockdown of Cysteine proteinase-1 (Cp1) in glia increased Drosophila alcohol sedation and that this effect was specific to cortex glia and adulthood. These data implicate Cp1 and cortex glia in alcohol-related behaviors. Cortex glia are functionally homologous to mammalian astrocytes and Cp1 is orthologous to mammalian Cathepsin L. Our studies raise the possibility that cathepsins may influence behavioral responses to alcohol in mammals via roles in astrocytes.
Investigating wind turbine dynamic transient loads using contactless shaft torque measurements
Authors: Zappalá Donatella , Crabtree Christopher J. , Hogg Simon 
Published: July 2019

The wind industry is showing increasing awareness about the importance of long‐term direct shaft mechanical torque measurements to fully understand wind turbine (WT) dynamics, adopt proactive solutions for extreme load mitigation and enhance condition monitoring (CM) capabilities. Although torsional effects are important, torque measurement on such large, inaccessible machines is practically and logistically difficult, mainly because of the costly and intrusive specialised equipment currently available. This study details an experimental set‐up for the investigation of shaft dynamic transient load and speed measurements through a contactless, low‐cost torque meter. Results are obtained over a range of applied loads and compared with reference measurements from an in‐line, invasive torque transducer. Average torque and speed root‐mean‐square error values of 0.53 Nm and 0.35 rpm, respectively, indicate good accuracy of the proposed contactless torque meter. Its implementation in the field would allow direct, cheap, real‐time measurements of WT drive train loads for performance monitoring, control and CM purposes.
The diagnostic potential of the weak field approximation for investigating the quiet Sun magnetism: the Si I 10 827 Å line
Authors: Shchukina N. G. , Trujillo Bueno J. 
Published: July 2019

Aims. We aim to investigate the validity of the weak field approximation (WFA) for determining magnetic fields in quiet regions of the solar photosphere using the polarization caused by the Zeeman effect in the Si I10 827 Å line.Methods. We solved the NLTE line formation problem by means of multilevel radiative transfer calculations in a three-dimensional (3D) snapshot model taken from a state-of-the-art magneto-convection simulation of the small-scale magnetic activity in the quiet solar photosphere. The 3D model used is characterized by a surface mean magnetic field strength of about 170 G. The calculated Stokes profiles were degraded because of the atmospheric turbulence of Earth and light diffraction by the telescope aperture. We apply the WFA to the StokesI,Q,U,Vprofiles calculated for different seeing conditions and for the apertures of the VTT, GREGOR, EST and DKIST telescopes. We compare the inferred longitudinal and transverse components of the magnetic field with the original vertical and horizontal fields of the 3D model.Results. We find that with a spatial resolution significantly better than 0.5″ the surface maps of the magnetic field inferred from the Stokes profiles of the Si I10 827 Å line applying the WFA are close to the magnetic field of the model on the corrugated surface, corresponding to line optical depth unity at Δλ ≈ 0.1 Å for a disk-center line of sight. The correlation between them is relatively high, except that the inferred longitudinal and transverse components of the magnetic field turn out to be lower than in the 3D model.Conclusions. The use of the WFA for interpreting high-spatial-resolution spectropolarimetric observations of the Si I10 827 Å line obtained with telescopes like GREGOR, EST, and DKIST allows the longitudinal and transverse components of the magnetic field to be retrieved with reasonable precision over the whole quiet solar photosphere, the result being worse for telescopes of lower aperture.