bluuebunny/crossref_metadata_2025 huggingface dataset:
Were changes in stress state responsible for the 2019 Ridgecrest, California, earthquakes?
Authors: Nanjo K. Z.
Published: June 2020

Monitoring the Earth’s stress state plays a role in our understanding of an earthquake’s mechanism and in the distribution of hazards. Crustal deformation due to the July 2019 earthquake sequence in Ridgecrest (California) that culminated in a preceding quake of magnitude (M) 6.4 and a subsequent M7.1 quake caused stress perturbation in a nearby region, but implications of future seismicity are still uncertain. Here, the occurrence of small earthquakes is compared to larger ones, using b-values, showing that the rupture initiation from an area of low b-values, indicative of high stress, was common to both M6.4 and M7.1 quakes. The post-M7.1-quake sequence reveals that another low-b-value zone, which avoided its ruptured area, fell into an area near the Garlock fault that hosted past large earthquakes. If this area were more stressed, there would be a high-likelihood of further activation of seismicity that might influence the Garlock fault.
Unconventional Hund metal in a weak itinerant ferromagnet
Authors: Chen Xiang , Krivenko Igor , Stone Matthew B. , Kolesnikov Alexander I. , Wolf Thomas , Reznik Dmitry , Bedell Kevin S. , Lechermann Frank , Wilson Stephen D.
Published: June 2020

The physics of weak itinerant ferromagnets is challenging due to their small magnetic moments and the ambiguous role of local interactions governing their electronic properties, many of which violate Fermi-liquid theory. While magnetic fluctuations play an important role in the materials’ unusual electronic states, the nature of these fluctuations and the paradigms through which they arise remain debated. Here we use inelastic neutron scattering to study magnetic fluctuations in the canonical weak itinerant ferromagnet MnSi. Data reveal that short-wavelength magnons continue to propagate until a mode crossing predicted for strongly interacting quasiparticles is reached, and the local susceptibility peaks at a coherence energy predicted for a correlated Hund metal by first-principles many-body theory. Scattering between electrons and orbital and spin fluctuations in MnSi can be understood at the local level to generate its non-Fermi liquid character. These results provide crucial insight into the role of interorbital Hund’s exchange within the broader class of enigmatic multiband itinerant, weak ferromagnets.
Pile-up transmission and reflection of topological defects at grain boundaries in colloidal crystals
Authors: Cao Xin , Panizon Emanuele , Vanossi Andrea , Manini Nicola , Tosatti Erio , Bechinger Clemens
Published: June 2020

Crystalline solids typically contain large amounts of defects such as dislocations and interstitials. How they travel across grain boundaries (GBs) under external stress is crucial to understand the mechanical properties of polycrystalline materials. Here, we experimentally and theoretically investigate with single-particle resolution how the atomic structure of GBs affects the dynamics of interstitial defects driven across monolayer colloidal polycrystals. Owing to the complex inherent GB structure, we observe a rich dynamical behavior of defects near GBs. Below a critical driving force defects cannot cross GBs, resulting in their accumulation near these locations. Under certain conditions, defects are reflected at GBs, leading to their enrichment at specific regions within polycrystals. The channeling of defects within samples of specifically-designed GB structures opens up the possibility to design novel materials that are able to confine the spread of damage to certain regions.
Modifying angular and polarization selection rules of high-order harmonics by controlling electron trajectories in k-space
Authors: Sanari Yasuyuki , Otobe Tomohito , Kanemitsu Yoshihiko , Hirori Hideki
Published: June 2020

Recent advances in generation of strong laser pulses have enabled the acceleration of electrons in solids into regions far away from the band edge. Because nonlinear currents can be generated by laser-driven carriers in the non-parabolic region, tailored laser fields may allow control of optical properties of high-order harmonics (HHs). So far, investigations on laser-induced nonlinear optical phenomena have focused on the simple electron motion induced by linearly or elliptically polarized fields. However, more complex trajectories can be important for development of novel optoelectronic devices. Here, we show that a weak laser field (optical frequency is ω2) applied in a direction orthogonal to a strong main field (ω1) enhances certain HH intensity components of bulk GaSe by a factor of 100. Good agreement between the experiments and calculations shows that manipulation of the electron trajectory allows breaking inversion symmetry of the electronic states felt by the accelerated electrons and leading to a modification of selection rules for frequency-mixing processes of HHs. Owing to our usage of non-integer multiples for ω1 and ω2, it is found that the generation of HHs constitutes a novel way of ultrafast control of light polarization and optical switching.
Cryo-EM structures of HKU2 and SADS-CoV spike glycoproteins provide insights into coronavirus evolution
Authors: Yu Jinfang , Qiao Shuyuan , Guo Runyu , Wang Xinquan
Published: June 2020

Porcine coronavirus SADS-CoV has been identified from suckling piglets with severe diarrhea in southern China in 2017. The SADS-CoV genome shares ~95% identity to that of bat α-coronavirus HKU2, suggesting that SADS-CoV may have emerged from a natural reservoir in bats. Here we report the cryo-EM structures of HKU2 and SADS-CoV spike (S) glycoprotein trimers at 2.38 Å and 2.83 Å resolution, respectively. We systematically compare the domains of HKU2 spike with those of α-, β-, γ-, and δ-coronavirus spikes, showing that the S1 subunit N- and C-terminal domains of HKU2/SADS-CoV are ancestral domains in the evolution of coronavirus spike proteins. The connecting region after the fusion peptide in the S2 subunit of HKU2/SADS-CoV adopts a unique conformation. These results structurally demonstrate a close evolutionary relationship between HKU2/SADS-CoV and β-coronavirus spikes and provide insights into the evolution and cross-species transmission of coronaviruses.
Post-surgical adhesions are triggered by calcium-dependent membrane bridges between mesothelial surfaces
Authors: Fischer Adrian , Koopmans Tim , Ramesh Pushkar , Christ Simon , Strunz Maximilian , Wannemacher Juliane , Aichler Michaela , Feuchtinger Annette , Walch Axel , Ansari Meshal , Theis Fabian J. , Schorpp Kenji , Hadian Kamyar , Neumann Philipp-Alexander , Schiller Herbert B. , Rinkevich Yuval
Published: June 2020

Surgical adhesions are bands of scar tissues that abnormally conjoin organ surfaces. Adhesions are a major cause of post-operative and dialysis-related complications, yet their patho-mechanism remains elusive, and prevention agents in clinical trials have thus far failed to achieve efficacy. Here, we uncover the adhesion initiation mechanism by coating beads with human mesothelial cells that normally line organ surfaces, and viewing them under adhesion stimuli. We document expansive membrane protrusions from mesothelia that tether beads with massive accompanying adherence forces. Membrane protrusions precede matrix deposition, and can transmit adhesion stimuli to healthy surfaces. We identify cytoskeletal effectors and calcium signaling as molecular triggers that initiate surgical adhesions. A single, localized dose targeting these early germinal events completely prevented adhesions in a preclinical mouse model, and in human assays. Our findings classifies the adhesion pathology as originating from mesothelial membrane bridges and offer a radically new therapeutic approach to treat adhesions.
Preparation of hundreds of microscopic atomic ensembles in optical tweezer arrays
Authors: Wang Yibo , Shevate Sayali , Wintermantel Tobias Martin , Morgado Manuel , Lochead Graham , Whitlock Shannon
Published: June 2020

We present programmable two-dimensional arrays of microscopic atomic ensembles consisting of more than 400 sites with nearly uniform filling and small atom number fluctuations. Our approach involves direct projection of light patterns from a digital micromirror device with high spatial resolution onto an optical pancake trap acting as a reservoir. This makes it possible to load large arrays of tweezers in a single step with high occupation numbers and low power requirements per tweezer. Each atomic ensemble is confined to ~1 μm3 with a controllable occupation from 20 to 200 atoms and with (sub)-Poissonian atom number fluctuations. Thus, they are ideally suited for quantum simulation and for realizing large arrays of collectively encoded Rydberg-atom qubits for quantum information processing.
Assessing morphological congruence in Dinobryon species and their stomatocysts, including a newly established Dinobryon pediforme–stomatocyst connection
Authors: Piątek Jolanta , Lenarczyk Joanna , Piątek Marcin
Published: June 2020

The chrysophyte genus Dinobryon Ehrenberg consists of 44 taxa, which occur in freshwaters, rarely marine waters, mostly in temperate regions of the world. The taxa of Dinobryon produce characteristic solitary or dendroid colonies and resting stages called stomatocysts. Only 20 Dinobryon taxa have information on produced stomatocysts and only four stomatocysts are reliably linked with vegetative stages using modern identification standards employing scanning electron microscopy (SEM) analyses. In this study, an encysted material of Dinobryon pediforme (Lemmermann) Steinecke was collected in two lakes in contrasting regions of Poland. Light microscopy (LM) and scanning electron microscopy (SEM) analyses revealed that Dinobryon pediforme produces stomatocyst #61, Piątek J. that is described here as new morphotype following the International Statospore Working Group (ISWG) guidelines. This raises to five the number of reliable links between vegetative stages of Dinobryon species and corresponding stomatocysts. Phenotypic similarities between Dinobryon species and their stomatocysts, analysed for five reliably established links, showed no relationships in size and shape between loricas and stomatocysts belonging to the same species. The morphological characters of loricas and stomatocysts mapped onto the phylogenetic tree of the five Dinobryon species revealed only little congruence between their morphology and phylogenetic relationships.
Unsupervised generative and graph representation learning for modelling cell differentiation
Authors: Bica Ioana , Andrés-Terré Helena , Cvejic Ana , Liò Pietro
Published: June 2020

Using machine learning techniques to build representations from biomedical data can help us understand the latent biological mechanism of action and lead to important discoveries. Recent developments in single-cell RNA-sequencing protocols have allowed measuring gene expression for individual cells in a population, thus opening up the possibility of finding answers to biomedical questions about cell differentiation. In this paper, we explore unsupervised generative neural methods, based on the variational autoencoder, that can model cell differentiation by building meaningful representations from the high dimensional and complex gene expression data. We use disentanglement methods based on information theory to improve the data representation and achieve better separation of the biological factors of variation in the gene expression data. In addition, we use a graph autoencoder consisting of graph convolutional layers to predict relationships between single-cells. Based on these models, we develop a computational framework that consists of methods for identifying the cell types in the dataset, finding driver genes for the differentiation process and obtaining a better understanding of relationships between cells. We illustrate our methods on datasets from multiple species and also from different sequencing technologies.
Genomic deregulation of PRMT5 supports growth and stress tolerance in chronic lymphocytic leukemia
Authors: Schnormeier Ann-Kathrin , Pommerenke Claudia , Kaufmann Maren , Drexler Hans G. , Koeppel Max
Published: June 2020

Patients suffering from chronic lymphocytic leukemia (CLL) display highly diverse clinical courses ranging from indolent cases to aggressive disease, with genetic and epigenetic features resembling this diversity. Here, we developed a comprehensive approach combining a variety of molecular and clinical data to pinpoint translocation events disrupting long-range chromatin interactions and causing cancer-relevant transcriptional deregulation. Thereby, we discovered a B cell specific cis-regulatory element restricting the expression of genes in the associated locus, including PRMT5 and DAD1, two factors with oncogenic potential. Experimental PRMT5 inhibition identified transcriptional programs similar to those in patients with differences in PRMT5 abundance, especially MYC-driven and stress response pathways. In turn, such inhibition impairs factors involved in DNA repair, sensitizing cells for apoptosis. Moreover, we show that artificial deletion of the regulatory element from its endogenous context resulted in upregulation of corresponding genes, including PRMT5. Furthermore, such disruption renders PRMT5 transcription vulnerable to additional stimuli and subsequently alters the expression of downstream PRMT5 targets. These studies provide a mechanism of PRMT5 deregulation in CLL and the molecular dependencies identified might have therapeutic implementations.
Shotgun proteomics reveals putative polyesterases in the secretome of the rock-inhabiting fungus Knufia chersonesos
Authors: Tesei Donatella , Quartinello Felice , Guebitz Georg M. , Ribitsch Doris , Nöbauer Katharina , Razzazi-Fazeli Ebrahim , Sterflinger Katja
Published: June 2020

Knufia chersonesos is an ascomycotal representative of black fungi, a morphological group of polyextremotolerant melanotic fungi, whose ability to resort to recalcitrant carbon sources makes it an interesting candidate for degradation purposes. A secretome screening towards polyesterases was carried out for the fungus and its non-melanized mutant, grown in presence of the synthetic copolyester Polybutylene adipate terephthalate (PBAT) as additional or sole carbon source, and resulted in the identification of 37 esterolytic and lipolytic enzymes across the established cultivation conditions. Quantitative proteomics allowed to unveil 9 proteins being constitutively expressed at all conditions and 7 which were instead detected as up-regulated by PBAT exposure. Protein functional analysis and structure prediction indicated similarity of these enzymes to microbial polyesterases of known biotechnological use such as MHETase from Ideonella sakaiensis and CalA from Candida antarctica. For both strains, PBAT hydrolysis was recorded at all cultivation conditions and primarily the corresponding monomers were released, which suggests degradation to the polymer’s smallest building block. The work presented here aims to demonstrate how investigations of the secretome can provide new insights into the eco-physiology of polymer degrading fungi and ultimately aid the identification of novel enzymes with potential application in polymer processing, recycling and degradation.
Quantification of node importance in rain gauge network: influence of temporal resolution and rain gauge density
Authors: Tiwari Shubham , Jha Sanjeev Kumar , Singh Ankit
Published: June 2020

Rain gauge network is important for collecting rainfall information effectively and efficiently. Rain gauge networks have been studied for several decades from a range of hydrological perspectives, where rain gauges with unique or non-repeating information are considered as important. However, the problem of quantification of node importance and subsequent identification of the most important nodes in rain gauge networks have not yet been extensively addressed in the literature. In this study, we use the concept of the complex networks to evaluate the Indian Meteorological Department (IMD) monitored 692 rain gauge in the Ganga River Basin. We consider the complex network theory-based Degree Centrality (DC), Clustering Coefficient (CC) and Mutual Information (MI) as the parameters to quantify the rainfall variability associated with all the rain gauges in the network. Multiple rain gauge network scenario with varying rain gauge density (i.e. Network Size (NS) = 173, 344, 519, and 692) and Temporal Resolution (i.e. TR = 3 hours, 1 day, and 1 month) are introduced to study the effect of rain gauge density, gauge location and temporal resolution on the node importance quantification. Proxy validation of the methodology was done using a hydrological model. Our results indicate that the network density and temporal resolution strongly influence a node’s importance in rain gauge network. In addition, we concluded that the degree centrality along with clustering coefficient is the preferred parameter than the mutual information for the node importance quantification. Furthermore, we observed that the network properties (spatial distribution, DC, Collapse Correlation Threshold (CCT), CC Range distributions) associated with TR = 3 hours and 1 day are comparable whereas TR = 1 month exhibit completely different trends. We also found that the rain gauges situated at high elevated areas are extremely important irrespective of the NS and TR. The encouraging results for the quantification of nodes importance in this study seem to indicate that the approach has the potential to be used in extreme rainfall forecasting, in studying changing rainfall patterns and in filling gaps in spatial data. The technique can be further helpful in the ground-based observation network design of a wide range of meteorological parameters with spatial correlation.
A new image encryption scheme based on coupling map lattices with mixed multi-chaos
Authors: Wang Xingyuan , Guan Nana , Zhao Hongyu , Wang Siwei , Zhang Yingqian
Published: June 2020

As a kind of spatiotemporal chaos, coupled map lattice (CML) is widely applied into image encryption because of its advantages of more complex dynamical behavior and lower computational overhead. Firstly, this paper proposed a novel spatiotemporal chaos model (MCML) by mixing Logistic, Sine and Tent maps into CML map together. Beyond that, we also change the structure of CML and the coupling method in different lattices. Bifurcation diagram, Lyapunov exponents and NIST test are employed to measure the chaotic behaviors of the MCML system. Secondly, by applying MCML chaos, we design a new key binding and distribution rule, the improved diffusion scheme to encrypt image. Furthermore, the novel bit Z-scan scrambling method also be used to enhance the security of the encryption scheme. Finally, a large number of experimental results prove that our proposed scheme is suitable for image encryption and has high security against common attacks.
High resolution spatial analyses of trace elements in coccoliths reveal new insights into element incorporation in coccolithophore calcite
Authors: Bottini Cinzia , Dapiaggi Monica , Erba Elisabetta , Faucher Giulia , Rotiroti Nicola
Published: June 2020

Coccolithophores are phytoplanktonic algae which produce an exoskeleton made of single platelets of calcite named coccoliths. They are widespread in all oceans and directly impact the short- and long-term C cycle. The study of coccolith size, morphology and elemental composition reveals important information regarding the ability of the cell to calcify and on the factors that influence this process. In this regard, very little is known about coccolith composition and its changes under altered environmental conditions. Here, we present high resolution (50 × 50 nm) elemental spatial distribution in pristine coccoliths of Coccolithus pelagicus and Gephyrocapsa oceanica reconstructed via X-ray fluorescence analyses at synchrotron. The studied specimens are from control culture and metal-enriched (V, Ni, Zn and Pb) experiments. The analysed specimens produced under stress conditions, display an irregular shape and are thinner, especially in the external rim, with ca. 1/3 lower Ca concentrations compared to specimens from the control. The same specimens also have higher Sr/Ca ratio with highest values in the coccolith external rim, suggesting that difficulty in calcification is additionally reflected in increased Sr/Ca ratios. Selenium is found in the coccolith as possible substitute of carbonate in the calcite. V and Pb apparently did not interact with the coccoliths while Zn and Ni were deposited on the coccolith surface.
Associations among neurophysiology measures in irritable bowel syndrome (IBS) and their relevance for IBS symptoms
Authors: Midenfjord Irina , Polster Annikka , Sjövall Henrik , Friberg Peter , Törnblom Hans , Simrén Magnus
Published: June 2020

Abnormal gut-brain interactions are common in irritable bowel syndrome (IBS), but the associations between neurophysiological measures and their relation to gastrointestinal (GI) symptoms are poorly understood. Our aim was to explore these relationships and define the most relevant neurophysiology measures for GI symptom severity in IBS. IBS patients underwent small intestinal motility (manometry; fasted and fed contraction frequency, phase III time) and secretion (transmural potential difference), rectal sensorimotor (barostat; sensory thresholds, tone response, compliance), autonomic nervous system (baroreceptor sensitivity and effectiveness), and colonic motor function (transit time) examinations. GI symptom severity (GSRS-IBS), and anxiety and depression (HAD) as a proxy measure of central nervous system (CNS) dysfunction, were assessed. In total 281 IBS patients (Rome II criteria) were included (74% females, median age 36 [interquartile range 28–50] years). Significant correlations between neurophysiology measures were stronger within, rather than between, different neurophysiological examinations. The strongest neurophysiology-symptom correlations occurred between a combination of CNS and visceral sensitivity parameters, and GSRS-IBS total score and pain domain (ρ = 0.40, p < 0.001, and ρ = 0.38, p < 0.001). Associations between GI symptoms in IBS and individual and combinations of neurophysiological factors occurred, primarily in CNS and visceral sensitivity measures, providing new insights into the clinical presentation of IBS.
Premises of social cognition: Newborns are sensitive to a direct versus a faraway gaze
Authors: Guellaï Bahia , Hausberger Martine , Chopin Adrien , Streri Arlette
Published: June 2020

Previous studies evidenced that already from birth, newborns can perceive differences between a direct versus an averted gaze in faces both presented in static and interactive situations. It has been hypothesized that this early sensitivity would rely on modifications of the location of the iris (i.e. the darker part of the eye) in the sclera (i.e. the white part), or that it would be an outcome of newborns’ preference for configurations of faces with the eye region being more contrasted. One question still remains: What happens when the position of the iris is not modified in the sclera, but the look is ‘faraway’, that is when the gaze is toward the newborns’ face but above his or her own eyes? In the present study, we tested the influence of a direct versus a faraway gaze (i.e., two gazes that only differed slightly in the position of the iris on the vertical axis and not on the horizontal axis) on newborns’ face recognition. The procedure was identical to that used in previous studies: using a familiarization-test procedure, we familiarized two groups of newborns (N = 32) with videos of different talking faces that were presented with either a direct or a faraway gaze. Newborns were then tested with photographs of the face seen previously and of a new one. Results evidenced that newborns looked longer at the familiar face, but only in the direct gaze condition. These results suggest that, already from birth, infants can perceive slight differences of gazes when someone is addressing to them.
Fusing α and β subunits of the fungal fatty acid synthase leads to improved production of fatty acids
Authors: Wernig Florian , Born Sandra , Boles Eckhard , Grininger Martin , Oreb Mislav
Published: June 2020

Most fungal fatty acid synthases assemble from two multidomain subunits, α and β, into a heterododecameric FAS complex. It has been recently shown that the complex assembly occurs in a cotranslational manner and is initiated by an interaction between the termini of α and β subunits. This initial engagement of subunits may be the rate-limiting phase of the assembly and subject to cellular regulation. Therefore, we hypothesized that bypassing this step by genetically fusing the subunits could be beneficial for biotechnological production of fatty acids. To test the concept, we expressed fused FAS subunits engineered for production of octanoic acid in Saccharomyces cerevisiae. Collectively, our data indicate that FAS activity is a limiting factor of fatty acid production and that FAS fusion proteins show a superior performance compared to their split counterparts. This strategy is likely a generalizable approach to optimize the production of fatty acids and derived compounds in microbial chassis organisms.
Inhibition of G protein-gated K+ channels by tertiapin-Q rescues sinus node dysfunction and atrioventricular conduction in mouse models of primary bradycardia
Authors: Bidaud Isabelle , Chong Antony Chung You , Carcouet Agnes , Waard Stephan De , Charpentier Flavien , Ronjat Michel , Waard Michel De , Isbrandt Dirk , Wickman Kevin , Vincent Anne , Mangoni Matteo E. , Mesirca Pietro
Published: June 2020

Sinus node (SAN) dysfunction (SND) manifests as low heart rate (HR) and is often accompanied by atrial tachycardia or atrioventricular (AV) block. The only currently available therapy for chronic SND is the implantation of an electronic pacemaker. Because of the growing burden of SND in the population, new pharmacological therapies of chronic SND and heart block are desirable. We developed a collection of genetically modified mouse strains recapitulating human primary SND associated with different degrees of AV block. These mice were generated with genetic ablation of L-type Cav1.3 (Cav1.3−/−), T-type Cav3.1 (Cav3.1−/−), or both (Cav1.3−/−/Cav3.1−/−). We also studied mice haplo-insufficient for the Na+ channel Nav1.5 (Nav1.5+/) and mice in which the cAMP-dependent regulation of hyperpolarization-activated f-(HCN4) channels has been abolished (HCN4-CNBD). We analysed, by telemetric ECG recording, whether pharmacological inhibition of the G-protein-activated K+ current (IKACh) by the peptide tertiapin-Q could improve HR and AV conduction in these mouse strains. Tertiapin-Q significantly improved the HR of Cav1.3−/− (19%), Cav1.3−/−/Cav3.1−/− (23%) and HCN4-CNBD (14%) mice. Tertiapin-Q also improved cardiac conduction of Nav1.5+/− mice by 24%. Our data suggest that the development of pharmacological IKACh inhibitors for the management of SND and conduction disease is a viable approach.
The effects of environmental enrichment on skin barrier recovery in humans: a randomised trial
Authors: Law Mikaela , Jarrett Paul , Nater Urs M. , Skoluda Nadine , Broadbent Elizabeth
Published: June 2020

This study investigated whether environmental enrichment (EE) could reduce stress and improve wound healing in humans. 120 participants underwent a standardised tape-stripping procedure and were then randomised to interact for 30 minutes with one of three EE interventions (comfort blankets as tactile enrichment, music as auditory enrichment or a Paro robot as multi-sensory enrichment) or to a control group. Skin barrier recovery (SBR) was measured using transepidermal water loss at baseline, after tape-stripping and after the intervention. Psychological variables, cortisol and alpha-amylase were measured at the three time-points. SBR did not significantly differ between the EE conditions and the control condition. The music condition had higher stimulation levels than the control condition, and the comfort condition had significantly lower relaxation levels than the control condition after the intervention. The EE interventions tested were not beneficial for wound healing compared to a control group. Limitations were that the sample were not stressed and an active control condition was used.
Acyl homoserine lactone-mediated quorum sensing in the oral cavity: a paradigm revisited
Authors: Muras Andrea , Otero-Casal Paz , Blanc Vanessa , Otero Ana
Published: June 2020

Acyl homoserine lactones (AHLs), the quorum sensing (QS) signals produced by Gram-negative bacteria, are currently considered to play a minor role in the development of oral biofilm since their production by oral pathogens has not been ascertained thus far. However, we report the presence of AHLs in different oral samples and their production by the oral pathogen Porphyromonas gingivalis. The importance of AHLs is further supported by a very high prevalence of AHL-degradation capability, up to 60%, among bacteria isolated from dental plaque and saliva samples. Furthermore, the wide-spectrum AHL-lactonase Aii20J significantly inhibited oral biofilm formation in different in vitro biofilm models and caused important changes in bacterial composition. Besides, the inhibitory effect of Aii20J on a mixed biofilm of 6 oral pathogens was verified using confocal microscopy. Much more research is needed in order to be able to associate specific AHLs with oral pathologies and to individuate the key actors in AHL-mediated QS processes in dental plaque formation. However, these results indicate a higher relevance of the AHLs in the oral cavity than generally accepted thus far and suggest the potential use of inhibitory strategies against these signals for the prevention and treatment of oral diseases.
Natural Regeneration in the Tumbesian Dry Forest: Identification of the Drivers Affecting Abundance and Diversity
Authors: Cueva-Ortiz Jorge , Espinosa Carlos Iván , Aguirre-Mendoza Zhofre , Gusmán-Montalván Elizabeth , Weber Michael , Hildebrandt Patrick
Published: June 2020

Tropical and subtropical dry forests make up the world’s largest terrestrial ecosystem. However, these forests have been used to establish several productive activities, such as growing crops, rearing livestock, and using the forest resources, due to their ease of access and climatic conditions, which has led to this ecosystem becoming highly threatened. Therefore, this research assessed the effects of anthropogenic pressures and a number of abiotic variables on natural regeneration in dry forests in the Tumbesian region by addressing three research questions: (a) What is the status of natural regeneration in terms of abundance and diversity? (b) Does livestock grazing and the anthropogenic pressure affect the abundance and diversity of natural regeneration? (c) Does seasonality or grazing have the greatest influence on the regeneration dynamics? Data were obtained from 72 samples (36 fenced and 36 unfenced) during five surveys spanning a 2-year period, and the seedling abundance, mortality, recruitment, species richness and diversity were evaluated using linear mixed models. Natural regeneration was most positively affected by rainy season precipitation, but soil conditions also played an important role. Short-term fences had a major effect on reducing mortality but did not improve the abundance or diversity, whereas cattle grazing significantly affected the abundance of seedlings.
Psychological distress and lack of PINK1 promote bioenergetics alterations in peripheral blood mononuclear cells
Authors: Grigoruţă Mariana , Dagda Ruben K. , Díaz-Sánchez Ángel G. , Martínez-Martínez Alejandro
Published: June 2020

Psychological distress induces oxidative stress and alters mitochondrial metabolism in the nervous and immune systems. Psychological distress promotes alterations in brain metabolism and neurochemistry in wild-type (WT) rats in a similar manner as in Parkinsonian rats lacking endogenous PTEN-induced kinase 1 (PINK1), a serine/threonine kinase mutated in a recessive forms of Parkinson’s disease. PINK1 has been extensively studied in the brain, but its physiological role in peripheral tissues and the extent to which it intersects with the neuroimmune axis is not clear. We surmised that PINK1 modulates the bioenergetics of peripheral blood mononuclear cells (PBMCs) under basal conditions or in situations that promote oxidative stress as psychological distress. By using an XF metabolic bioanalyzer, PINK1-KO-PBMCs showed significantly increased oxidative phosphorylation and basal glycolysis compared to WT cells and correlated with motor dysfunction. In addition, psychological distress enhanced the glycolytic capacity in PINK1-KO-PBMCs but not in WT-PBMCs. The level of antioxidant markers and brain-derived neurotrophic factor were altered in PINK1-KO-PBMCs and by psychological distress. In summary, our data suggest that PINK1 is critical for modulating the bioenergetics and antioxidant responses in PBMCs whereas lack of PINK1 upregulates compensatory glycolysis in response to oxidative stress induced by psychological distress.
GTP hydrolysis by Synechocystis IM30 does not decisively affect its membrane remodeling activity
Authors: Junglas Benedikt , Siebenaller Carmen , Schlösser Lukas , Hellmann Nadja , Schneider Dirk
Published: June 2020

The function of IM30 (also known as Vipp1) is linked to protection and/or remodeling of the thylakoid membrane system in chloroplasts and cyanobacteria. Recently, it has been revealed that the Arabidopsis IM30 protein exhibits GTP hydrolyzing activity in vitro, which was unexpected, as IM30 does not show any classical GTPase features. In the present study, we addressed the question, whether an apparent GTPase activity is conserved in IM30 proteins and can also be observed for IM30 of the cyanobacterium Synechocystis sp. PCC 6803. We show that Synechocystis IM30 is indeed able to bind and hydrolyze GTP followed by the release of Pi. Yet, the apparent GTPase activity of Synechocystis IM30 does not depend on Mg2+, which, together with the lack of classical GTPase features, renders IM30 an atypical GTPase. To elucidate the impact of this cryptic GTPase activity on the membrane remodeling activity of IM30, we tested whether GTP hydrolysis influences IM30 membrane binding and/or IM30-mediated membrane fusion. We show that membrane remodeling by Synechocystis IM30 is slightly affected by nucleotides. Yet, despite IM30 clearly catalyzing GTP hydrolysis, this does not seem to be vital for its membrane remodeling function.
A general-purpose Monte Carlo particle transport code based on inverse transform sampling for radiotherapy dose calculation
Authors: Liang Ying , Muhammad Wazir , Hart Gregory R. , Nartowt Bradley J. , Chen Zhe J. , Yu James B. , Roberts Kenneth B. , Duncan James S. , Deng Jun
Published: June 2020

The Monte Carlo (MC) method is widely used to solve various problems in radiotherapy. There has been an impetus to accelerate MC simulation on GPUs whereas thread divergence remains a major issue for MC codes based on acceptance-rejection sampling. Inverse transform sampling has the potential to eliminate thread divergence but it is only implemented for photon transport. Here, we report a MC package Particle Transport in Media (PTM) to demonstrate the implementation of coupled photon-electron transport simulation using inverse transform sampling. Rayleigh scattering, Compton scattering, photo-electric effect and pair production are considered in an analogous manner for photon transport. Electron transport is simulated in a class II condensed history scheme, i.e., catastrophic inelastic scattering and Bremsstrahlung events are simulated explicitly while subthreshold interactions are subject to grouping. A random-hinge electron step correction algorithm and a modified PRESTA boundary crossing algorithm are employed to improve simulation accuracy. Benchmark studies against both EGSnrc simulations and experimental measurements are performed for various beams, phantoms and geometries. Gamma indices of the dose distributions are better than 99.6% for all the tested scenarios under the 2%/2 mm criteria. These results demonstrate the successful implementation of inverse transform sampling in coupled photon-electron transport simulation.
An integrative approach for pediatric auditory neuropathy spectrum disorders: revisiting etiologies and exploring the prognostic utility of auditory steady-state response
Authors: Lin Pei-Hsuan , Hsu Chuan-Jen , Lin Yin-Hung , Lin Yi-Hsin , Yang Shu-Yu , Yang Ting-Hua , Chen Pei-Lung , Wu Chen-Chi , Liu Tien-Chen
Published: June 2020

Auditory neuropathy is an important entity in childhood sensorineural hearing loss. Due to diverse etiologies and clinical features, the management is often challenging. This study used an integrative patient-history, audiologic, genetic, and imaging-based approach to investigate the etiologies and audiologic features of 101 children with auditory neuropathy. Etiologically, 48 (47.5%), 16 (15.8%), 11 (10.9%), and 26 (25.7%) children were categorized as having acquired, genetic, cochlear nerve deficiency-related, and indefinite auditory neuropathy, respectively. The most common causes of acquired and genetic auditory neuropathy were prematurity and OTOF mutations, respectively. Patients with acquired auditory neuropathy presented hearing loss earlier (odds ratio, 10.2; 95% confidence interval, 2.2–47.4), whereas patients with genetic auditory neuropathy had higher presence rate of distortion product otoacoustic emissions (odds ratio, 10.7; 95% confidence interval, 1.3–85.4). In patients with different etiologies or pathological sites, moderate to strong correlations (Pearson’s r = 0.51–0.83) were observed between behavioral thresholds and auditory steady-state response thresholds. In conclusion, comprehensive assessments can provide etiological clues in ~75% of the children with auditory neuropathy. Different etiologies are associated with different audiologic features, and auditory steady-state responses might serve as an objective measure for estimating behavioral thresholds.
Identification of eQTLs associated with lipid metabolism in Longissimus dorsi muscle of pigs with different genetic backgrounds
Authors: Criado-Mesas Lourdes , Ballester Maria , Crespo-Piazuelo Daniel , Castelló Anna , Fernández Ana I. , Folch Josep M.
Published: June 2020

Intramuscular fat content and its fatty acid composition affect porcine meat quality and its nutritional value. The present work aimed to identify genomic variants regulating the expression in the porcine muscle(Longissimus dorsi)of 45 candidate genes for lipid metabolism and fatty acid composition in three experimental backcrosses based on the Iberian breed. Expression genome-wide association studies (eGWAS) were performed between the muscle gene expression values, measured by real-time quantitative PCR, and the genotypes of 38,426 SNPs distributed along all chromosomes. The eGWAS identified 186 eSNPs located in tenSus scrofaregions and associated with the expression ofACSM5,ACSS2,ATF3,DGAT2,FOSandIGF2(FDR < 0.05) genes. Two expression quantitative trait loci (eQTLs) forIGF2andACSM5were classified ascis-acting eQTLs, suggesting a mutation in the same gene affecting its expression. Conversely, ten eQTLs showedtrans-regulatory effects on gene expression. When the eGWAS was performed for each backcross independently, only three commontrans-eQTL regions were observed, indicating different regulatory mechanisms or allelic frequencies among the breeds. In addition, hotspot regions regulating the expression of several genes were detected. Our results provide new data to better understand the functional regulatory mechanisms of lipid metabolism genes in muscle.
Nutritional value, antioxidant and antidiabetic properties of nettles (Laportea alatipes and Obetia tenax)
Authors: Mahlangeni Nomfundo Thobeka , Moodley Roshila , Jonnalagadda Sreekantha Babu
Published: June 2020

Nettles are commonly consumed in South Africa, Europe and Asia and are used in traditional medicine to treat a variety of ailments. In this study, the nutritional value of the leaves of nettles (Laportea alatipes and Obetia tenax) was evaluated and compared, when cooked and uncooked. The results showed a decrease in the concentrations of crude protein, vitamin A, vitamin E and metals after cooking of nettles. Although cooking reduced the concentrations of essential elements in nettles, their contribution to the diet remained adequate. L. alatipes presented with reduced levels of Cd (from 1.86 to 0.810 mg kg−1) and Pb (from 2.87 to 1.88 mg kg−1) after cooking. Similarly, Cd (from 2.97 to 0.780 mg kg−1) and Pb (from 2.21 to 0.795 mg kg−1) levels in O. tenax decreased after cooking, demonstrating the significance of cooking. The antioxidant activity of the nettles was determined using the 2,2-diphenyl-l-picrylhydrazyl (DPPH) free radical and ferric reducing antioxidant power (FRAP) assays. The methanol extract of Obetia tenax showed high ferric reducing power whilst the radical scavenging activity was due to the presence of the bioactive molecule, β-carotene, in the plants which exhibited higher DPPH radical scavenging ability relative to test samples and standards. The in vitro antidiabetic activity of the extracts and compounds from the nettles was better than or comparable to that of the known standard, acarbose, which underscores the prospective antidiabetic properties of nettles. Overall, our study provides scientific validation for the ethno-medicinal use of nettles and supports their consumption, which highlights their potential as nutraceuticals.
Dual plasmonic nanostructures for switching polarity of hot electron-induced photocurrent
Authors: Hu Taozheng , Wu Jingyu , Han Diyi , Ni Yaxian , Dong Wen , Chen Zhuo , Wang Zhenlin
Published: June 2020

We report on the experimental investigation of polarity-switchable hot electron-induced photocurrents in dual-plasmonic nanostructures, consisting of two layers of gold nanoparticles (AuNPs) separated by a TiO2film.
Templating S100A9 amyloids on Aβ fibrillar surfaces revealed by charge detection mass spectrometry, microscopy, kinetic and microfluidic analyses
Authors: Pansieri Jonathan , Iashchishyn Igor A. , Fakhouri Hussein , Ostojić Lucija , Malisauskas Mantas , Musteikyte Greta , Smirnovas Vytautas , Schneider Matthias M. , Scheidt Tom , Xu Catherine K. , Meisl Georg , Knowles Tuomas P. J. , Gazit Ehud , Antoine Rodolphe , Morozova-Roche Ludmilla A.
Published: June 2020

Templating mechanism of S100A9 amyloids on Aβ fibrillar surfaces during amyloid co-aggregation process was revealed by synergy of biophysical methods including charge detection mass spectrometry, microscopy, kinetic and microfluidic analyses.
A fluorescent probe based on reversible Michael addition–elimination reaction for the cycle between cysteine and H2O2
Authors: Liu Feiran , Zang Shunping , Jing Jing , Zhang Xiaoling
Published: June 2020

A reversible fluorescent probe for rapidly and specifically detecting the reaction of cysteine and H2O2.
Catalysis to discriminate single atoms from subnanometric ruthenium particles in ultra-high loading catalysts
Authors: Rivera-Cárcamo C. , Leng F. , Gerber I. C. , del Rosal I. , Poteau R. , Collière V. , Lecante P. , Nechiyil D. , Bacsa W. , Corrias A. , Axet M. R. , Serp P.
Published: June 2020

We report a procedure for preparing ultra-high metal loading (10–50% w/w Ru) Ru@C60 nanostructured catalysts comprising exclusively Ru single atoms or mixtures of single atoms and clusters.
Plasma modified BiOCl/sulfonated graphene microspheres as efficient photo-compensated electrocatalysts for the oxygen evolution reaction
Authors: Lv Miao , Jin Shengming , Wang Hui , Chen Yumo , Ma Ting , Cui Kuixin , Li Junzhi , Wu Song , Liu Zhan , Guo Yanru , Liu Zhiliang , Chang Xinghua , Li Xingguo
Published: June 2020

Plasma regulation of oxygen vacancies in BiOCl/sulfonated graphene composites enables light energy compensation for the electrocatalytic OER process.
Low-cost desalination of seawater and hypersaline brine using nanophotonics enhanced solar energy membrane distillation
Authors: Said Ibrahim A. , Fuentes Naomi , He Ze , Xin Ruikun , Zuo Kuichang , Li Qilin
Published: June 2020

A stand-alone small-scale nanophotonics enhanced solar membrane distillation (NESMD) testbed was designed, developed, and tested for desalinating seawater and high salinity feedwaters.
Sauce it up: influence of condiment properties on oral processing behavior, bolus formation and sensory perception of solid foods
Authors: van Eck Arianne , Franks Erin , Vinyard Christopher J. , Galindo-Cuspinera Verónica , Fogliano Vincenzo , Stieger Markus , Scholten Elke
Published: June 2020

Foods are rarely consumed on their own. Food oral processing behavior and sensory perception of composite foods varying in properties were investigated in this study.
Protective effect and mechanism of Monascus-fermented red yeast rice against colitis caused by Salmonella enterica serotype Typhimurium ATCC 14028
Authors: Huang Ya-ping , Li Ping , Du Ting , Du Xin-jun , Wang Shuo
Published: June 2020

The effect of red yeast rice on Salmonella enterica-induced intestinal inflammation and gut microbiota dysbiosis in mice as well as the underlying mechanism.
A yolk–albumen–shell structure of mixed Ni–Co oxide with an ultrathin carbon shell for high-sensitivity glucose sensors
Authors: Zhang Xuan , Zhang Yawei , Guo Wei , Wan Kai , Zhang Ting , Arbiol Jordi , Zhao Yong-Qing , Xu Cai-Ling , Xu Maowen , Fransaer Jan
Published: June 2020

Non-enzymatic glucose sensors based on different Co–Ni–C composite materials were developed by pyrolysis of bimetallic or single metal based metal–organic frameworks (MOFs).
Mn(ii) chelate-coated superparamagnetic iron oxide nanocrystals as high-efficiency magnetic resonance imaging contrast agents
Authors: Wu Changqiang , Chen Tianwu , Deng Lihua , Xia Qian , Chen Chuan , Lan Mu , Pu Yu , Tang Hongjie , Xu Ye , Zhu Jiang , Xu Chenjie , Shen Chengyi , Zhang Xiaoming
Published: June 2020

In this communication, a paramagnetic bifunctional manganese(ii) chelate ([Mn(Dopa-EDTA)]2−) containing a catechol group is synthesized and coated on the surface of SPIO nanocrystals.
Polyelectrolyte stiffness on gold nanorods mediates cell membrane damage
Authors: Azman Nurul ‘Ain , Bekale Laurent , Nguyen Thanh Xuan , Kah James Chen Yong
Published: June 2020

CGMD showed that ligand mechanical stability which resulted in the exposure of the hydrophobic AuNR core, disrupted the lipid bilayer organization. The damage was confirmed using hemolysis assay whereby lipid bilayer disruption resulted in the release of hemoglobin.
Autogenic single p/n-junction solar cells from black-Si nano-grass structures of p-to-n type self-converted electronic configuration
Authors: Das Debajyoti , Karmakar Laxmikanta
Published: June 2020

One-step fabrication of autogenic single p/n-junction b-Si nano-grass ‘proof-of-concept’ solar cells is realized; photovoltaic performance improves via absorber-layer itself acting as anti-reflection nanostructure with enhanced active absorber area.
Modular and scalable synthesis of nematode pheromone ascarosides: implications in eliciting plant defense response
Authors: Ning Shuai , Zhang Lei , Ma Jinjin , Chen Lan , Zeng Guangyao , Yang Chao , Zhou Yingjun , Guo Xiaoli , Deng Xu
Published: June 2020

An efficient and modular access to ascarosides was developed, which also provides valuable insights into their SARs in eliciting plant defense response.
Arylseleninic acid as a green, bench-stable selenylating agent: synthesis of selanylanilines and 3-selanylindoles
Authors: Abenante Laura , Padilha Nathalia B. , Anghinoni João M. , Penteado Filipe , Rosati Ornelio , Santi Claudio , Silva Marcio S. , Lenardão Eder J.
Published: June 2020

C–Se bonds in electron-rich arenes are easily formed by the reaction of bench-stable arylseleninic acids as an electrophilic selenium source. The only waste in the reaction is water.