bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synchrony and asynchrony between an epigenetic clock and developmental timing
Authors: Hoshino Akina , Horvath Steve , Sridhar Akshayalakshmi , Chitsazan Alex , Reh Thomas A. 
Published: March 2019

AbstractEpigenetic changes have been used to estimate chronological age across the lifespan, and some studies suggest that epigenetic “aging” clocks may already operate in developing tissue. To better understand the relationship between developmental stage and epigenetic age, we utilized the highly regular sequence of development found in the mammalian neural retina and a well-established epigenetic aging clock based on DNA methylation. Our results demonstrate that the epigenetic age of fetal retina is highly correlated with chronological age. We further establish that epigenetic aging progresses normally in vitro, suggesting that epigenetic aging is a property of individual tissues. This correlation is also retained in stem cell-derived retinal organoids, but is accelerated in individuals with Down syndrome, a progeroid-like condition. Overall, our results suggest that epigenetic aging begins as early as a few weeks post-conception, in fetal tissues, and the mechanisms underlying the phenomenon of epigenetic aging might be studied in developing organs.
Induced high-temperature ferromagnetism by structural phase transitions in strained antiferromagnetic γ-Fe50Mn50 epitaxial films
Authors: Hwang Younghun , Choi Sungyoul , Choi Jeongyong , Cho Sunglae 
Published: March 2019

AbstractStrain effects in epitaxial films can substantially enhance individual functional properties or induce properties which do not exist in corresponding bulk materials. The bcc α-Fe50Mn50 films are a ferromagnetic with a Curie temperature between 650 K and 750 K, which do not exist in nature can be manipulated through the tensile strain. In this study, γ-Fe50Mn50 epitaxial films grown on GaAs(001) using molecular beam epitaxy are found to structural transition from the face-centered-cubic (fcc, a = 0.327 nm) γ-phase to the body-centered-cubic (bcc, a = 0.889 nm) α-phase. For α-Fe50Mn50 epitaxial films, ferromagnetism is accompanied by structural phase transition due to the tensile strain induced by the differences of the thermal expansion between the film and the substrate. Moreover, by realizing in epitaxial films with fcc structure a tensile strain state, phase transitions were introduced Fe-Mn alloy system with bcc structure. These findings are of fundamental importance to understanding the mechanism of phase transition and properties of epitaxial CuAu-I type antiferromagnetic alloy thin films under strain.
Spike sorting with Gaussian mixture models
Authors: Souza Bryan C. , Lopes-dos-Santos Vítor , Bacelo João , Tort Adriano B. L. 
Published: March 2019

AbstractThe shape of extracellularly recorded action potentials is a product of several variables, such as the biophysical and anatomical properties of the neuron and the relative position of the electrode. This allows isolating spikes of different neurons recorded in the same channel into clusters based on waveform features. However, correctly classifying spike waveforms into their underlying neuronal sources remains a challenge. This process, called spike sorting, typically consists of two steps: (1) extracting relevant waveform features (e.g., height, width), and (2) clustering them into non-overlapping groups believed to correspond to different neurons. In this study, we explored the performance of Gaussian mixture models (GMMs) in these two steps. We extracted relevant features using a combination of common techniques (e.g., principal components, wavelets) and GMM fitting parameters (e.g., Gaussian distances). Then, we developed an approach to perform unsupervised clustering using GMMs, estimating cluster properties in a data-driven way. We found the proposed GMM-based framework outperforms previously established methods in simulated and real extracellular recordings. We also discuss potentially better techniques for feature extraction than the widely used principal components. Finally, we provide a friendly graphical user interface to run our algorithm, which allows manual adjustments.
Rare Pathogenic Variants Predispose to Hepatocellular Carcinoma in Nonalcoholic Fatty Liver Disease
Authors: Pelusi Serena , Baselli Guido , Pietrelli Alessandro , Dongiovanni Paola , Donati Benedetta , McCain Misti Vanette , Meroni Marica , Fracanzani Anna Ludovica , Romagnoli Renato , Petta Salvatore , Grieco Antonio , Miele Luca , Soardo Giorgio , Bugianesi Elisabetta , Fargion Silvia , Aghemo Alessio , D’Ambrosio Roberta , Xing Chao , Romeo Stefano , De Francesco Raffaele , Reeves Helen Louise , Valenti Luca Vittorio Carlo 
Published: March 2019

AbstractNonalcoholic fatty liver disease (NAFLD) is a rising cause of hepatocellular carcinoma (HCC). We examined whether inherited pathogenic variants in candidate genes (n = 181) were enriched in patients with NAFLD-HCC. To this end, we resequenced peripheral blood DNA of 142 NAFLD-HCC, 59 NAFLD with advanced fibrosis, and 50 controls, and considered 404 healthy individuals from 1000 G. Pathogenic variants were defined according to ClinVar, likely pathogenic as rare variants predicted to alter protein activity. In NAFLD-HCC patients, we detected an enrichment in pathogenic (p = 0.024), and likely pathogenic variants (p = 1.9*10−6), particularly in APOB (p = 0.047). APOB variants were associated with lower circulating triglycerides and higher HDL cholesterol (p < 0.01). A genetic risk score predicted NAFLD-HCC (OR 4.96, 3.29–7.55; p = 5.1*10−16), outperforming the diagnostic accuracy of common genetic risk variants, and of clinical risk factors (p < 0.05). In conclusion, rare pathogenic variants in genes involved in liver disease and cancer predisposition are associated with NAFLD-HCC development.
Elaboration Benefits Source Memory Encoding Through Centrality Change
Authors: Amlien Inge K. , Sneve Markus H. , Vidal-Piñeiro Didac , Walhovd Kristine B. , Fjell Anders M. 
Published: March 2019

AbstractVariations in levels of processing affect memory encoding and subsequent retrieval performance, but it is unknown how processing depth affects communication patterns within the network of interconnected brain regions involved in episodic memory encoding. In 113 healthy adults scanned with functional MRI, we used graph theory to calculate centrality indices representing the brain regions’ relative importance in the memory network. We tested how communication patterns in 42 brain regions involved in episodic memory encoding changed as a function of processing depth, and how these changes were related to episodic memory ability. Centrality changes in right middle frontal gyrus, right inferior parietal lobule and left superior frontal gyrus were positively related to semantic elaboration during encoding. In the same regions, centrality during successful episodic memory encoding was related to performance on the episodic memory task, indicating that these centrality changes reflect processes that support memory encoding through deep elaborative processing. Similar analyses were performed for congruent trials, i.e. events that fit into existing knowledge structures, but no relationship between centrality changes and congruity were found. The results demonstrate that while elaboration and congruity have similar beneficial effects on source memory performance, the cortical signatures of these processes are probably not identical.
TGR5 activation ameliorates hyperglycemia-induced cardiac hypertrophy in H9c2 cells
Authors: Cheng Kai-Chun , Chang Wei-Ting , Kuo Feng Yu , Chen Zhih-Cherng , Li Yingxiao , Cheng Juei-Tang 
Published: March 2019

AbstractLeft ventricular hypertrophy is an independent risk factor in diabetic patients. TGR5 is shown to express in hearts, but its functional role in diabetes-induced cardiac hypertrophy remained unclear. The current study investigated the role of TGR5 on high glucose-induced hypertrophy of H9C2 cells. After incubation with a high level of glucose, H9C2 cells showed hypertrophic responses. Activation of TGR5 by lithocholic acid (LCA) ameliorated cell hypertrophy and enhanced SERCA2a and phosphorylated phospholamban (PLN) expression in H9C2 cells. Triamterene inhibited these effects at an effective dose to block TGR5. However, LCA failed to modify the free radical elevation induced by high-glucose in the H9c2 cells. Moreover, PKA inhibitors, but not an Epac blocker, markedly improved hyperglycemia-induced hypertrophy and attenuated the increased SERCA2a expression by LCA; it also attenuated the phosphorylated PLN and SERCA2a protein expression levels in high glucose-treated H9C2 cells. In conclusion, TGR5 activation stimulated protein kinase A (PKA) to enhance PLN phosphorylation, which activated SERCA2a to remove Ca2+ from cytosol to sarcoplasmic reticulum in addition to the reduction of calcineurin/NFAT pathway signaling to ameliorate the hyperglycemia-induced cardiac hypertrophy shown in cardiomyocytes. TGR5 may service as a new target in the control of diabetic cardiomyopathy.
Single-Shot Multi-Frame Imaging of Cylindrical Shock Waves in a Multi-Layered Assembly
Authors: Dresselhaus-Cooper Leora , Gorfain Joshua E. , Key Chris T. , Ofori-Okai Benjamin K. , Ali Suzanne J. , Martynowych Dmitro J. , Gleason Arianna , Kooi Steven , Nelson Keith A. 
Published: March 2019

AbstractWe demonstrate single-shot multi-frame imaging of quasi-2D cylindrically converging shock waves as they propagate through a multi-layer target sample assembly. We visualize the shock with sequences of up to 16 images, using a Fabry-Perot cavity to generate a pulse train that can be used in various imaging configurations. We employ multi-frame shadowgraph and dark-field imaging to measure the amplitude and phase of the light transmitted through the shocked target. Single-shot multi-frame imaging tracks geometric distortion and additional features in our images that were not previously resolvable in this experimental geometry. Analysis of our images, in combination with simulations, shows that the additional image features are formed by a coupled wave structure resulting from interface effects in our targets. This technique presents a new capability for tabletop imaging of shock waves that can be extended to experiments at large-scale facilities.
Experimental Microwave Scattering in Polygonal Billiards
Authors: Carmo R. B. do , Aguiar F. M. de 
Published: March 2019

AbstractFluctuations in the one-port scattering and normalized impedance matrices in three polygonal and one chaotic time-reversal invariant microwave billiards are experimentally investigated, in several levels of coupling and absorption, at room temperature and at 77 K. The observed distributions of reflection coefficient, phase of the scattering matrix, resistance and reactance exhibit no fingerprint of a given geometry. At low frequencies, the results are consistent with earlier theoretical models by López, Mello and Seligman and by Zheng, Antonsen and Ott, who independently predicted that the scattering fluctuations might be the same for the Wigner and Poisson level spacing distributions in the lossless cavity. The uniqueness of the observed scattering statistics at higher absorption levels is discussed with respect to inherent limitations posed by the experimental technique.
Carrier Transport and Recombination Mechanism in Blue Phosphorescent Organic Light-Emitting Diode with Hosts Consisting of Cabazole- and Triazole-Moiety
Authors: Cheng Tian-You , Lee Jiun-Haw , Chen Chia-Hsun , Chen Po-Hsun , Wang Po-Sheng , Lin Chuan-En , Lin Bo-Yen , Lan Yi-Hsin , Hsieh Yu-Hsuan , Huang Jau-Jiun , Lu Hsiu-Feng , Chao Ito , Leung Man-kit , Chiu Tien-Lung , Lin Chi-Feng 
Published: March 2019

AbstractIn this study, we demonstrated a blue phosphorescent organic light-emitting diode (BPOLED) based on a host with two carbazole and one trizole (2CbzTAZ) moiety, 9,9′-(2-(4,5-diphenyl-4H-1,2,4-triazol-3-yl)-1,3-phenylene)bis(9H-carbazole), that exhibits bipolar transport characteristics. Compared with the devices with a carbazole host (N,N’-dicarbazolyl-3,5-benzene, (mCP)), triazole host (3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole, (TAZ)), or a physical mixture of mCP:TAZ, which exhibit hole, electron, and bipolar transport characteristics, respectively, the BPOLED with the bipolar 2CbzTAZ host exhibited the lowest driving voltage (6.55 V at 10 mA/cm2), the highest efficiencies (maximum current efficiency of 52.25 cd/A and external quantum efficiency of 23.89%), and the lowest efficiency roll-off, when doped with bis[2-(4,6-difluorophenyl)pyridinato-C2,N](picolinato)iridium(III) (FIrpic) as blue phosphor. From analyses of light leakage of the emission spectra of electroluminescence, transient electroluminescence, and partially doped OLEDs, it was found that the recombination zone was well confined inside the emitting layer and the recombination rate was most efficient in a 2CbzTAZ-based OLED. For the other cases using mCP, TAZ, and mCP:TAZ as hosts, electrons and holes transported with different routes that resulted in carrier accumulation on different organic molecules and lowered the recombination rate.
Movement of environmental threats modifies the relevance of the defensive eye-blink in a spatially-tuned manner
Authors: Somervail R. , Bufacchi R. J. , Guo Y. , Kilintari M. , Novembre G. , Swapp D. , Steed A. , Iannetti G. D. 
Published: March 2019

AbstractSubcortical reflexive motor responses are under continuous cortical control to produce the most effective behaviour. For example, the excitability of brainstem circuitry subserving the defensive hand-blink reflex (HBR), a response elicited by intense somatosensory stimuli to the wrist, depends on a number of properties of the eliciting stimulus. These include face-hand proximity, which has allowed the description of an HBR response field around the face (commonly referred to as a defensive peripersonal space, DPPS), as well as stimulus movement and probability of stimulus occurrence. However, the effect of stimulus-independent movements of objects in the environment has not been explored. Here we used virtual reality to test whether and how the HBR-derived DPPS is affected by the presence and movement of threatening objects in the environment. In two experiments conducted on 40 healthy volunteers, we observed that threatening arrows flying towards the participant result in DPPS expansion, an effect directionally-tuned towards the source of the arrows. These results indicate that the excitability of brainstem circuitry subserving the HBR is continuously adjusted, taking into account the movement of environmental objects. Such adjustments fit in a framework where the relevance of defensive actions is continually evaluated, to maximise their survival value.
Self-rated health and the risk of incident type 2 diabetes mellitus: A cohort study
Authors: Noh Jin-Won , Chang Yoosoo , Park Minsun , Kwon Young Dae , Ryu Seungho 
Published: March 2019

AbstractWe aimed to evaluate the association between self-rated health (SRH) and the risk of incident type 2 diabetes mellitus (T2D). This cohort study consisted of 250,805 Korean men and women without T2D at baseline. SRH was assessed at baseline with a self-administered structured questionnaire. Incident T2D was defined as fasting serum glucose ≥126 mg/dL, HbA1C ≥6.5%, or use of medication for T2D during follow-up. After adjustment for possible confounders including age, center, year of screening exam, smoking status, alcohol intake, physical activity, education level, total calorie intake, body mass index, sleep duration, depressive symptoms, family history of diabetes, history of hypertension, and history of cardiovascular disease, the multivariable-adjusted hazard ratios (95% confidence intervals) for incident T2D comparing good, fair, and poor or very poor SRH to very good SRH were 1.20 (0.98–1.48), 1.63 (1.33–1.98), and 1.83 (1.47–2.27), respectively. These associations were consistently observed in clinically relevant subgroups. Fair or poorer SRH was independently and positively associated with the development of T2D in a large-scale cohort study of apparently healthy Korean adults, indicating that SRH is a predictor of metabolic health. Physicians involved in diabetes screening and management should routinely consider SRH when evaluating T2D risk as well as overall health.
Proteomic changes in oocytes after in vitro maturation in lipotoxic conditions are different from those in cumulus cells
Authors: Marei Waleed F. A. , Van Raemdonck Geert , Baggerman Geert , Bols Peter E. J. , Leroy Jo L. M. R. 
Published: March 2019

AbstractMaternal lipolytic metabolic disorders result in a lipotoxic microenvironment in the ovarian follicular fluid (FF) which deteriorates oocyte quality. Although cellular stress response mechanisms are well defined in somatic cells, they remain largely unexplored in oocytes, which have distinct organelle structure and nuclear transcription patterns. Here we used shotgun proteomic analyses to study cellular responses of bovine oocytes and cumulus cells (CCs) after in vitro maturation under lipotoxic conditions; in the presence of pathophysiological palmitic acid (PA) concentration as a model. Differentially regulated proteins (DRPs) were mainly localized in the endoplasmic reticulum, mitochondria and nuclei of CCs and oocytes, however the DRPs and their direction of change were cell-type specific. Proteomic changes in PA-exposed CCs were predominantly pro-apoptotic unfolded protein responses (UPRs), mitochondrial and metabolic dysfunctions, and apoptotic pathways. This was also functionally confirmed. Interestingly, although the oocytes were enclosed by CCs during PA exposure, elevated cellular stress levels were also evident. However, pro-survival UPRs, redox regulatory and compensatory metabolic mechanisms were prominent despite evidence of mitochondrial dysfunction, oxidative stress, and reduced subsequent embryo development. The data provides a unique insight that enriches the understanding of the cellular stress responses in metabolically-compromised oocytes and forms a fundamental base to identify new targets for fertility treatments as discussed within.
Microplastic deposition velocity in streams follows patterns for naturally occurring allochthonous particles
Authors: Hoellein Timothy J. , Shogren Arial J. , Tank Jennifer L. , Risteca Paul , Kelly John J. 
Published: March 2019

AbstractAccumulation of plastic litter is accelerating worldwide. Rivers are a source of microplastic (i.e., particles <5 mm) to oceans, but few measurements of microplastic retention in rivers exist. We adapted spiraling metrics used to measure particulate organic matter transport to quantify microplastic deposition using an outdoor experimental stream. We conducted replicated pulse releases of three common microplastics: polypropylene pellets, polystyrene fragments, and acrylic fibers, repeating measurements using particles with and without biofilms. Depositional velocity (vdep; mm/s) patterns followed expectations based on density and biofilm ‘stickiness’, where vdep was highest for fragments, intermediate for fibers, and lowest for pellets, with biofilm colonization generally increasing vdep. Comparing microplastic vdep to values for natural particles (e.g., fine and coarse particulate organic matter) showed that particle diameter was positively related to vdep and negatively related to the ratio of vdep to settling velocity (i.e., sinking rate in standing water). Thus, microplastic vdep in rivers can be quantified with the same methods and follows the same patterns as natural particles. These data are the first measurements of microplastic deposition in rivers, and directly inform models of microplastic transport at the landscape scale, making a key contribution to research on the global ecology of plastic waste.
Unravelling paralogous gene expression dynamics during three-spined stickleback embryogenesis
Authors: Kaitetzidou Elisavet , Katsiadaki Ioanna , Lagnel Jacques , Antonopoulou Efthimia , Sarropoulou Elena 
Published: March 2019

AbstractDevelopment requires the implementation of a plethora of molecular mechanisms, involving a large set of genes to ensure proper cell differentiation, morphogenesis of tissues and organs as well as the growth of the organism. Genome duplication and resulting paralogs are considered to provide the raw genetic materials important for new adaptation opportunities and boosting evolutionary innovation. The present study investigated paralogous genes, involved in three-spined stickleback (Gasterosteus aculeatus) development. Therefore, the transcriptomes of five early stages comprising developmental leaps were explored. Obtained expression profiles reflected the embryo’s needs at different stages. Early stages, such as the morula stage comprised transcripts mainly involved in energy requirements while later stages were mostly associated with GO terms relevant to organ development and morphogenesis. The generated transcriptome profiles were further explored for differential expression of known and new paralogous genes. Special attention was given to hox genes, with hoxa13a being of particular interest and to pigmentation genes where itgb1, involved in the melanophore development, displayed a complementary expression pattern throughout studied stages. Knowledge obtained by untangling specific paralogous gene functions during development might not only significantly contribute to the understanding of teleost ontogenesis but might also shed light on paralogous gene evolution.
Insecticidal activity of Vanillosmopsis arborea essential oil and of its major constituent α-bisabolol against Callosobruchus maculatus (Coleoptera: Chrysomelidae)
Authors: Moura Eridiane da Silva , Faroni Lêda Rita D’ Antonino , Zanuncio José Cola , Heleno Fernanda Fernandes , Prates Lucas Henrique Figueiredo 
Published: March 2019

AbstractVigna unguiculata, one of the most important legumes, mainly in underdeveloped countries, is susceptible to post-harvest losses in storage by Callosobruchus maculatus (Fabricius, 1775) (Coleoptera: Chrysomelidae). The work evaluated the toxicity, inhibition of oviposition, instantaneous rate of population growth (ri) and the development of fumigated C. maculatus with the essential oil of Vanillosmopsis arborea and its major constituent, α-bisabolol. The experimental units consisted of 0.8 L flasks treated with concentrations of 1.2–11.2 μL L−1of air of the essential oil of V. arborea or its major constituent applied to disks of filter paper. α-Bisabolol was quantified as 409.33 mL L−1 of the essential oil. The development rate of C. maculatus was evaluated by daily adult counts. Oviposition was evaluated at lethal concentrations (LC50, LC25, LC10 and LC1). The LC50 and LC95 of the essential oil of V. arborea and α-bisabolol were 5.23 and 12.97 μL L−1 of air and 2.47 and 8.82 μL L−1 of air, respectively. At some concentrations, the α-bisabolol was more toxic to males than to females of the insect. Increased concentrations of the essential oil reduced the ri, rate of development, oviposition, and number of eggs of C. maculatus and therefore have potential for pest control.
Highly efficient eco-friendly corrosion inhibitor for mild steel in 5 M HCl at elevated temperatures: experimental & molecular dynamics study
Authors: El-Haddad Muhsen A. M. , Bahgat Radwan A. , Sliem Mostafa H. , Hassan Walid M. I. , Abdullah Aboubakr M. 
Published: March 2019

AbstractLaurhydrazide N′-propan-3-one was used as an eco-friendly inhibitor for the corrosion of mild steel in 5 M HCl at elevated temperatures. Various electrochemical techniques and surface characterization methods were utilized in this study. In addition, the kinetics and thermodynamic parameters were calculated and discussed. Furthermore, a geometry optimization of LHP was performed and the time-dependent density functional theory was utilized to calculate the electronic absorption spectra. Finally, frequency calculations were, also, performed on the optimized geometry.