bluuebunny/crossref_metadata_2025_split huggingface dataset:
Offspring sex ratio and reproductive tactics of Leptocybe invasa (Hymenoptera: Eulophidae): testing the effect of environmental characteristics
Authors: Zheng Xia-Lin , Lin Kai , Huang Zong-You , Li Jun , Yang Zhen-De , Yang Xiu-Hao , Lu Wen 
Published: July 2018

AbstractEnvironmental characteristics (for example, temperature, photoperiod) as seasonal cues can affect the offspring sex ratio and reproductive tactics of many hymenopteran insects.Leptocybe invasaFisher &amp; La Salle is the most critical invasive insect pest ofEucalyptusspp. in the world and displays thelytokous reproduction. In the current study, we studied the effects of temperature and photoperiod on offspring sex ratio and reproductive tactics inL. invasa. Results show that sex ratio (female: male) ofL. invasawas under 15, 25 and 35 °C with both L 12: D 12 and L 16: D 8, and cold and thermal acclimation were 74.5:1, 71.0:1, 59.0:0, 17.3:1, 53.0:0, 64.0:0, 47.0:1 and 56.0:0, respectively, which was highly significantly female biased and with no significant difference due to temperature or photoperiod. Offspring virgin females oviposited and induced the bump-shaped galls on plants under the same conditions as described above. Constant temperature, photoperiod and their interaction, and cold and thermal acclimation had no significant effect on the infestation rates ofEucalyptusbranches induced by offspring virgin females. Thus, temperature, photoperiod and cold and thermal acclimation did not influence female-biased sex ratio and tactics with thelytokous reproduction of offspring females inL. invasa.
Solar Particle Event Dose Forecasting Using Regression Techniques
Authors: Lovelace Alan Mitchel , Rashid Al Maqsudur , de Wet Wouter C. , Townsend Lawrence W. , Wesley Hines J. , Moussa Hanna 
Published: July 2018

AbstractDoses from solar particle events can be a serious threat to the wellbeing of crews traveling through space. Therefore, methods for predicting the time such events will take place, methods for forecasting the dose buildup over time, and methods for forecasting the potential total dose from such events are needed to enable crews to take actions to mitigate the effects by entering a shielded area designed for their protection. This work focuses on forecasting the total dose expected for an event, based upon doses obtained very early in the event, using the kernel regression method. The model uses tables of calculated doses for historical solar particle events augmented with hypothetical events similar to the actual ones for training purposes. Reasonably accurate predictions of the total dose expected for an event can be made within the first hour after event onset. Predictive accuracies generally increase as the event progresses in time. The only inputs required are doses and times since event onset as provided by dosimetry devices. One hundred thirteen actual events with total doses between 1 and 1,000 cGy were tested using the model. At 1 hr into the event, total dose predictions were within ±30% of the actual total doses for 91 events (81%) and within ±15% for 54 of them (48%). Within the first 4 hr following event onset, total dose predictions were within ±30% for 98 events (87%) and within ±15% for 66 of them (58%). A software package implementing the model has been provided to the Space Radiation Analysis Group at NASA Johnson Space for incorporation into their operational procedures for analyzing possible threats to space crews from solar particle events.
Simulated Interannual Teleconnection Between the Summer North Atlantic Oscillation and Summer Precipitation in Eastern China During the Last Millennium
Authors: Peng Youbing 
Published: July 2018

AbstractThe interannual teleconnections between the summer North Atlantic Oscillation and summer precipitation in eastern China over the last millennium are investigated in a 1,000‐year simulation by the global climate model Community Climate System Model version 2.0.1. The model was able to roughly produce the general features of the teleconnection influences in eastern China, with negative (positive) precipitation anomalies north of 30°N and positive (negative) precipitation anomalies south of 30°N, associated with the positive (negative) phase of the North Atlantic Oscillation. The composite analysis reveals that the influence of the North Atlantic Oscillation on precipitation in summer in eastern China is chiefly via the “North Atlantic‐Eurasian teleconnection pattern,” which extends from the subtropical North Atlantic to East Asia.
Stress Concentrations in Weak Snowpack Layers and Conditions for Slab Avalanche Release
Authors: Gaume J. , Chambon G. , Herwijnen A. van , Schweizer J. 
Published: July 2018

AbstractDry‐snow slab avalanches release due to the formation of a crack in a weak layer buried below cohesive snow slabs, followed by rapid crack propagation. The onset of rapid crack propagation occurs if stresses at the crack tip in the weak layer overcome its strength. In this study, we use the finite element method to evaluate the maximum shear stress τmax induced by a preexisting crack in a weak snow layer allowing for the bending of the overlaying slab. It is shown that τmax increases with increasing crack length, slab thickness, slab density, weak layer elastic modulus, and slope angle. In contrast, τmax decreases with increasing elastic modulus of the slab. Assuming a realistic failure envelope, we computed the critical crack length ac for the onset of crack propagation. The model allows for remote triggering from flat (or low angle) terrain. Yet it shows that the critical crack length decreases with increasing slope angle.
An Empirical Dayglow Model for the Lyman‐Birge‐Hopfield‐Long Band Derived From the Polar Ultraviolet Imager Data
Authors: Wang Lingmin , Luan Xiaoli , Lei Jiuhou , Dou Xiankang 
Published: July 2018

AbstractThe Lyman‐Birge‐Hopfield‐long band dayglow emissions near 1,700 Å, which were observed by the ultraviolet imager on board Polar satellite, are characterized as a cosine‐like function of the solar zenith angle. These emissions are mainly excited by the solar extreme ultraviolet produced photoelectrons acting on the nitrogen molecules. The amplitude and phase factors are used to quantify the cosine‐like function and subsequently develop a dayglow model. In this study, a model is developed by considering broader dayglow emission areas outside the auroral oval, as the dayglow intensities in the dayside can exceed the auroral brightness, especially in summer. Also, this model is constructed by considering the seasonal variations of the two factors. It is demonstrated that, besides the strong solar cycle and universal time dependencies, the amplitude factors of the cosine‐like function show prominent seasonal variations, which are associated with the solar zenith angle changes. The amplitude factors are the largest in summer and smallest in winter. In addition, the dayglow phase factors show nearly constant values within each season, but throughout the year, they are higher in summer and equinoctial months and lower in winter. The dayglow model can benefit the investigation of global auroral patterns for all seasons.
Shaped 3D microcarriers for adherent cell culture and analysis
Authors: Wu Chueh-Yu , Stoecklein Daniel , Kommajosula Aditya , Lin Jonathan , Owsley Keegan , Ganapathysubramanian Baskar , Di Carlo Dino 
Published: July 2018

AbstractStandard tissue culture of adherent cells is known to poorly replicate physiology and often entails suspending cells in solution for analysis and sorting, which modulates protein expression and eliminates intercellular connections. To allow adherent culture and processing in flow, we present 3D-shaped hydrogel cell microcarriers, which are designed with a recessed nook in a first dimension to provide a tunable shear-stress shelter for cell growth, and a dumbbell shape in an orthogonal direction to allow for self-alignment in a confined flow, important for processing in flow and imaging flow cytometry. We designed a method to rapidly design, using the genetic algorithm, and manufacture the microcarriers at scale using a transient liquid molding optofluidic approach. The ability to precisely engineer the microcarriers solves fundamental challenges with shear-stress-induced cell damage during liquid-handling, and is poised to enable adherent cell culture, in-flow analysis, and sorting in a single format.
Genetic correlation network prediction of forest soil microbial functional organization
Authors: Ma Bin , Zhao Kankan , Lv Xiaofei , Su Weiqin , Dai Zhongmin , Gilbert Jack A , Brookes Philip C , Faust Karoline , Xu Jianming 
Published: July 2018

Abstract
Soil ecological functions are largely determined by the activities of soil microorganisms, which, in turn, are regulated by relevant interactions between genes and their corresponding pathways. Therefore, the genetic network can theoretically elucidate the functional organization that supports complex microbial community functions, although this has not been previously attempted. We generated a genetic correlation network based on 5421 genes derived from metagenomes of forest soils, identifying 7191 positive and 123 negative correlation relationships. This network consisted of 27 clusters enriched with sets of genes within specific functions, represented with corresponding cluster hubs. The clusters revealed a hierarchical architecture, reflecting the functional organization in the soil metagenomes. Positive correlations mapped functional associations, whereas negative correlations often mapped regulatory processes. The potential functions of uncharacterized genes were predicted based on the functions of located clusters. The global genetic correlation network highlights the functional organization in soil metagenomes and provides a resource for predicting gene functions. We anticipate that the genetic correlation network may be exploited to comprehensively decipher soil microbial community functions.
Manic Fringe deficiency imposes Jagged1 addiction to intestinal tumor cells
Authors: López-Arribillaga Erika , Rodilla Verónica , Colomer Carlota , Vert Anna , Shelton Amy , Cheng Jason H. , Yan Bing , Gonzalez-Perez Abel , Junttila Melissa R. , Iglesias Mar , Torres Ferran , Albanell Joan , Villanueva Alberto , Bigas Anna , Siebel Christian W. , Espinosa LLuís 
Published: July 2018

AbstractDelta ligands regulate Notch signaling in normal intestinal stem cells, while Jagged1 activates Notch in intestinal adenomas carrying active β-catenin. We used the ApcMin/+ mouse model, tumor spheroid cultures, and patient-derived orthoxenografts to address this divergent ligand-dependent Notch function and its implication in disease. We found that intestinal-specific Jag1 deletion or antibody targeting Jag1 prevents tumor initiation in mice. Addiction to Jag1 is concomitant with the absence of Manic Fringe (MFNG) in adenoma cells, and its ectopic expression reverts Jag1 dependence. In 239 human colorectal cancer patient samples, MFNG imposes a negative correlation between Jag1 and Notch, being high Jag1 in the absence of MFNG predictive of poor prognosis. Jag1 antibody treatment reduces patient-derived tumor orthoxenograft growth without affecting normal intestinal mucosa. Our data provide an explanation to Jag1 dependence in cancer, and reveal that Jag1–Notch1 interference provides therapeutic benefit in a subset of colorectal cancer and FAP syndrome patients.
New insights into the design of conjugated polymers for intramolecular singlet fission
Authors: Hu Jiahua , Xu Ke , Shen Lei , Wu Qin , He Guiying , Wang Jie-Yu , Pei Jian , Xia Jianlong , Sfeir Matthew Y. 
Published: July 2018

AbstractSinglet fission (SF), a multiple exciton generation process that generates two triplet excitons after the absorption of one photon, can potentially enable more efficient solar cell designs by harvesting energy normally lost as heat. While low-bandgap conjugated polymers are highly promising candidates for efficient SF-based solar cells, few polymer materials capable of SF have been reported because the SF process in polymer chains is poorly understood. Using transient spectroscopy, we demonstrate a new, highly efficient (triplet yield of 160–200%) isoindigo-based donor–acceptor polymer and show that the triplet pairs are directly emissive and exhibit a time-dependent energy evolution. Importantly, aggregation in poor solvents and in films significantly lowers the singlet energy, suppressing triplet formation because the energy conservation criterion is no longer met. These results suggest a new design rule for developing intramolecular SF capable low-bandgap conjugated polymers, whereby inter-chain interactions must be carefully engineered.
Fast Maximum Likelihood Estimation via Equilibrium Expectation for Large Network Data
Authors: Byshkin Maksym , Stivala Alex , Mira Antonietta , Robins Garry , Lomi Alessandro 
Published: July 2018

AbstractA major line of contemporary research on complex networks is based on the development of statistical models that specify the local motifs associated with macro-structural properties observed in actual networks. This statistical approach becomes increasingly problematic as network size increases. In the context of current research on efficient estimation of models for large network data sets, we propose a fast algorithm for maximum likelihood estimation (MLE) that affords a significant increase in the size of networks amenable to direct empirical analysis. The algorithm we propose in this paper relies on properties of Markov chains at equilibrium, and for this reason it is called equilibrium expectation (EE). We demonstrate the performance of the EE algorithm in the context of exponential random graph models (ERGMs) a family of statistical models commonly used in empirical research based on network data observed at a single period in time. Thus far, the lack of efficient computational strategies has limited the empirical scope of ERGMs to relatively small networks with a few thousand nodes. The approach we propose allows a dramatic increase in the size of networks that may be analyzed using ERGMs. This is illustrated in an analysis of several biological networks and one social network with 104,103 nodes.
High Dose Vitamin D supplementation alters faecal microbiome and predisposes mice to more severe colitis
Authors: Ghaly Simon , Kaakoush Nadeem O. , Lloyd Frances , McGonigle Terence , Mok Danny , Baird Angela , Klopcic Borut , Gordon Lavinia , Gorman Shelley , Forest Cynthia , Bouillon Roger , Lawrance Ian C. , Hart Prue H. 
Published: July 2018

AbstractVitamin D has been suggested as a possible adjunctive treatment to ameliorate disease severity in human inflammatory bowel disease. In this study, the effects of diets containing high (D++, 10,000 IU/kg), moderate (D+, 2,280 IU/kg) or no vitamin D (D−) on the severity of dextran sodium sulphate (DSS) colitis in female C57Bl/6 mice were investigated. The group on high dose vitamin D (D++) developed the most severe colitis as measured by blinded endoscopic (p < 0.001) and histologic (p < 0.05) assessment, weight loss (p < 0.001), drop in serum albumin (p = 0.05) and increased expression of colonic TNF-α (p < 0.05). Microbiota analysis of faecal DNA showed that the microbial composition of D++ control mice was more similar to that of DSS mice. Serum 25(OH)D3 levels reduced by 63% in the D++ group and 23% in the D+ group after 6 days of DSS treatment. Thus, high dose vitamin D supplementation is associated with a shift to a more inflammatory faecal microbiome and increased susceptibility to colitis, with a fall in circulating vitamin D occurring as a secondary event in response to the inflammatory process.
Novel application of In Vivo Micro-Optical Coherence Tomography to assess Cornea scarring in an Animal Model
Authors: Ang Marcus , Devarajan Kavya , Das Suchandrima , Yam Gary H. F. , Htoon Hla Mynt , Chen Si , Liu Xinyu , Liu Linbo , Girard Michael , Mehta Jodhbir S. 
Published: July 2018

AbstractThis pilot study uses a micro-optical coherence tomography (micro-OCT) system with ~1 μm axial resolution specifically to image the cornea and corneal scars in vivo. We used an established murine corneal scar model by irregular phototherapeutic keratectomy in ten C57BL/6 mice, with serial imaging using the micro-OCT and compared to anterior segment (AS-OCT) (RTvue, Optovue, Fremont, CA) before and after scar induction. Main outcome was agreement between the AS-OCT and micro-OCT using Bland-Altman plots (95% limits of agreement, LoA).We analysed 10 control eyes and 10 eyes with corneal scars and found that there was good agreement between AS-OCT and micro-OCT (P > 0.05) LOA: lower limit −14 µm (95% CI: −19 to −8.8 µm) upper limit 23 µm (95% CI: 18 to 28.5 µm) in terms of central corneal thickness. There was also good agreement between AS-OCT and micro-OCT in terms of corneal scar measurements (P > 0.5; correlation coefficient >0.99) LOA lower limit −2.1 µm (95% CI: −2.8 to −1.5 µm); upper limit 1.8 µm (95% CI: 1.1 to 2.4 µm). Our pilot study suggests that this novel in vivo micro-OCT imaging technique was able to measure central corneal thickness and scar thickness in agreement with current AS-OCT techniques.
A convex 3D deconvolution algorithm for low photon count fluorescence imaging
Authors: Ikoma Hayato , Broxton Michael , Kudo Takamasa , Wetzstein Gordon 
Published: July 2018

AbstractDeconvolution is widely used to improve the contrast and clarity of a 3D focal stack collected using a fluorescence microscope. But despite being extensively studied, deconvolution algorithms can introduce reconstruction artifacts when their underlying noise models or priors are violated, such as when imaging biological specimens at extremely low light levels. In this paper we propose a deconvolution method specifically designed for 3D fluorescence imaging of biological samples in the low-light regime. Our method utilizes a mixed Poisson-Gaussian model of photon shot noise and camera read noise, which are both present in low light imaging. We formulate a convex loss function and solve the resulting optimization problem using the alternating direction method of multipliers algorithm. Among several possible regularization strategies, we show that a Hessian-based regularizer is most effective for describing locally smooth features present in biological specimens. Our algorithm also estimates noise parameters on-the-fly, thereby eliminating a manual calibration step required by most deconvolution software. We demonstrate our algorithm on simulated images and experimentally-captured images with peak intensities of tens of photoelectrons per voxel. We also demonstrate its performance for live cell imaging, showing its applicability as a tool for biological research.
Modelling extreme desiccation tolerance in a marine tardigrade
Authors: Sørensen-Hygum Thomas L. , Stuart Robyn M. , Jørgensen Aslak , Møbjerg Nadja 
Published: July 2018

AbstractIt has recently been argued that the enigmatic tardigrades (water bears) will endure until the sun dies, surviving any astrophysical calamities in Earth’s oceans. Yet, our knowledge of stress tolerance among marine tardigrade species is very limited and most investigations revolve around species living in moist habitats on land. Here, we investigate desiccation tolerance in the cosmopolitan marine tidal tardigrade, Echiniscoides sigismundi, providing the first thorough analysis on recovery upon desiccation from seawater. We test the influence on survival of desiccation surface, time spent desiccated (up to 1 year) and initial water volume. We propose analysis methods for survival estimates, which can be used as a future platform for evaluating and analysing recovery rates in organisms subjected to extreme stress. Our data reveal that marine tidal tardigrades tolerate extremely rapid and extended periods of desiccation from seawater supporting the argument that these animals are among the toughest organisms on Earth.
The transcriptional factor ZEB1 represses Syndecan 1 expression in prostate cancer
Authors: Farfán Nancy , Ocarez Nallatt , Castellón Enrique A. , Mejía Nilo , de Herreros Antonio García , Contreras Héctor R. 
Published: July 2018

AbstractSyndecan 1 (SDC-1) is a cell surface proteoglycan with a significant role in cell adhesion, maintaining epithelial integrity. SDC1 expression is inversely related to aggressiveness in prostate cancer (PCa). During epithelial to mesenchymal transition (EMT), loss of epithelial markers is mediated by transcriptional repressors such as SNAIL, SLUG, or ZEB1/2 that bind to E-box promoter sequences of specific genes. The effect of these repressors on SDC-1 expression remains unknown. Here, we demonstrated that SNAIL, SLUG and ZEB1 expressions are increased in advanced PCa, contrarily to SDC-1. SNAIL, SLUG and ZEB1 also showed an inversion to SDC-1 in prostate cell lines. ZEB1, but not SNAIL or SLUG, represses SDC-1 as demonstrated by experiments of ectopic expression in epithelial prostate cell lines. Inversely, expression of ZEB1 shRNA in PCa cell line increased SDC-1 expression. The effect of ZEB1 is transcriptional since ectopic expression of this gene represses SDC-1 promoter activity and ZEB1 binds to the SDC-1 promoter as detected by ChIP assays. An epigenetic mark associated to transcription repression H3K27me3 was bound to the same sites that ZEB1. In conclusion, this study identifies ZEB1 as a key repressor of SDC-1 during PCa progression and point to ZEB1 as a potentially diagnostic marker for PCa.
The reciprocal interplay between TNFα and the circadian clock impacts on cell proliferation and migration in Hodgkin lymphoma cells
Authors: Abreu Mónica , Basti Alireza , Genov Nikolai , Mazzoccoli Gianluigi , Relógio Angela 
Published: July 2018

AbstractA bidirectional interaction between the circadian network and effector mechanisms of immunity brings on a proper working of both systems. In the present study, we used Hodgkin lymphoma (HL) as an experimental model for a type of cancer involving cells of the immune system. We identified this cancer type among haematological malignancies has having a strong differential expression of core-clock elements. Taking advantage of bioinformatics analyses and experimental procedures carried out in III- and IV-stage HL cells, and lymphoblastoid B cells, we explored this interplay and bear out diverse interacting partners of both systems. In particular, we assembled a wide-ranging network of clock-immune-related genes and pinpointed TNF as a crucial intermediary player. A robust circadian clock hallmarked III-stage lymphoma cells, differently from IV-stage HL cells, which do not harbour a properly functioning clockwork. TNF and circadian gene modulation impacted on clock genes expression and triggered phenotypic changes in lymphoma cells, suggesting a crucial involvement of core-clock elements and TNF in the physiopathological mechanisms hastening malignancy. Our results move forward our understanding of the putative role of the core-clock and TNF in the pathobiology of Hodgkin lymphoma, and highlight their influence in cellular proliferation and migration in lymphatic cancers.