393 research outputs found
Social Media Attention Increases Article Visits: An Investigation on Article-Level Referral Data of PeerJ
In order to better understand the effect of social media in the dissemination
of scholarly articles, employing the daily updated referral data of 110 PeerJ
articles collected over a period of 345 days, we analyze the relationship
between social media attention and article visitors directed by social media.
Our results show that social media presence of PeerJ articles is high. About
68.18% of the papers receive at least one tweet from Twitter accounts other
than @PeerJ, the official account of the journal. Social media attention
increases the dissemination of scholarly articles. Altmetrics could not only
act as the complement of traditional citation measures but also play an
important role in increasing the article downloads and promoting the impacts of
scholarly articles. There also exists a significant correlation among the
online attention from different social media platforms. Articles with more
Facebook shares tend to get more tweets. The temporal trends show that social
attention comes immediately following publication but does not last long, so do
the social media directed article views
Tandem mass spectrometryfor the determination of the sitesof DNA interstrand cross-link
Formation of DNA interstrand cross-link is implicated in the mechanism of anticancer activity of some drugs. Here we examined the fragmentation of deprotonated ions of double-stranded oligodeoxynucleotides (ODNs) that are covalently held together with either a mitomycin C or a 4,5′,8-trimethylpsoralen. Our results showed that, upon collisional activation, the covalently-bound duplex ODNs cleaved to give a series of wn and [an − base] ions; the sites of interstrand cross-linking could be determined from the mass shifts of some product ions. In addition, compared with the product-ion spectra acquired on an ion trap, those obtained from sustained off-resonance irradiation-collisionally activated dissociation (SORI-CAD) on a Fourier transform mass spectrometer offered high mass-resolving power, which facilitated unambiguous assignment of product ions and made it an effective method for locating the cross-linking sites
Implementation of Drone System in Survey for Tomato Chlorotic Spot Virus
As a cutting-edge technology, drone systems have shown great potential in agriculture. This article elucidates the implementation of a drone with a multispectral sensing system in a field survey for tomato chlorotic spot virus in south Florida. The findings demonstrate that drone technology can provide growers with precise and timely information about disease incidence and distribution in a labor-saving manner for decision making in crop management to mitigate yield loss. We provide recommendations for Extension professionals regarding educating producers on applying the technology to manage their crops efficiently
Fatigue Life Simulation and Analysis of Aluminum Alloy Sheet Self-piercing Riveting
The fatigue life prediction model of self-piecing riveting components of aluminum alloy is established and the effects of roughness and residual stress on fatigue life of self-piercing riveting components is analyzed by the model. Finite element software ABAQUS and fatigue analysis software FE-SAFE are used to study the effects of roughness and residual stress on the fatigue life of self-piecing riveting components through finite element simulation and mathematical statistics multivariate orthogonal regression experiment. The quantitative relations between fatigue life and three variables (roughness, residual stress and maximum stress) are fitted, and the variation trend of fatigue life with roughness and residual stress is obtained. The order of influence of roughness, residual stress, maximum stress and two interactions on fatigue life is as follows: residual stress, interaction between roughness and residual stress, roughness. When the maximum stress is fixed, the fatigue life decreases with the increase of roughness with a certain residual stress, and the fatigue life decreases with the increase of roughness with a certain residual stress. The average error between the fatigue experiment results and the simulation results is 9.74%, which proves that the simulation results are reliable
Describing Strong Correlation with Block-Correlated Coupled Cluster Theory
A block-correlated coupled cluster (BCCC) method based on the generalized
valence bond (GVB) wave function (GVB-BCCC in short) is proposed and
implemented at the ab initio level, which represents an attractive
multireference electronic structure method for strongly correlated systems. The
GVB-BCCC method is demonstrated to provide accurate descriptions for multiple
bond breaking in small molecules, although the GVB reference function is
qualitatively wrong for the studied processes. For a challenging prototype of
strongly correlated systems, tridecane with all 12 single C-C bonds at various
distances, our calculations have shown that the GVB-BCCC2b method can provide
highly comparable results as the density matrix renormalization group method
for potential energy surfaces along simultaneous dissociation of all C-C bonds
Effects of an allelochemical in Phaeodactylum tricornutum filtrate on Heterosigma akashiwo : morphological, physiological and growth effects
© The Author(s), 2017. This is the author's version of the work. It is posted here under a nonexclusive, irrevocable, paid-up, worldwide license granted to WHOI. It is made available for personal use, not for redistribution. The definitive version was published in Chemosphere 186 (2017): 527-534, doi:10.1016/j.chemosphere.2017.08.024.The effects of an allelochemical extracted from the culture filtrate of diatom Phaeodactylum
tricornutum on the raphidophyte Heterosigma akashiwo were investigated using a series of
morphological, physiological and biochemical characters. Growth experiments showed that H.
akashiwo was significantly inhibited immediately after exposure to the allelochemical, with many cells
rapidly dying and lysing based on microscopic observation. The effects of the allelochemical on the
surviving cells were explored using Scanning Electron Microscopy (SEM) and Flow cytometry (FCM),
the latter by examination of a suite of physiological parameters (membrane integrity, esterase activity,
chlorophyll-a content, membrane potential). The results demonstrate that the membrane of H. akashiwo
was attacked by the allelochemical directly, causing cell membrane breakage and loss of integrity.
Esterase activity was the most sensitive indicator of the impacts of the allelochemical. Membrane potential and chlorophyll-a content both showed significant decreases following exposure of the
Heterosigma cells to high concentrations of the allelochemical for 5 and 6 days. Both were affected,
but the membrane potential response was more gradual compared to other effects. The cell size of H.
akashiwo did not change compared with the control group. The surviving cells were able to continue to
grow and in a few days, re-establish a successful culture, even in the presence of residual
allelochemical, suggesting either development of cellular resistance, or the degradation of the chemical.The authors wish to thank the National Programme on Global Change and Air-Sea Interaction (Grant
No. GASI-03-01-02-01); the National Key Research and Development Program [Grant No.
2016YFC1402101]; the assessment of nanomaterials on biological and ecological effects in the coastal
area (Grant No. 201505034)
Large uniform copper 1,3,5-benzenetricarboxylate metal-organic-framework particles from slurry crystallization and their outstanding CO 2 gas adsorption capacity
To prepare more and better metal organic frameworks (MOFs) from less solvent for capturing greenhouse gas, a modified slurry crystallization (MSC) method has been first demonstrated for making MOF copper 1, 3, 5-benzenetricarboxylate from a solvent-deficient system. One outstanding advantage is its drastic reduction of solvent consumption and waste liquid in the whole synthesis. In a typical process, the mass ratio of ethanol to the solid reactants is ∼0.52, which is only about 0.35%–7.5% of that used in conventional processes. A high yield of ∼98.0% is easily achieved for the product with uniform size up to 160 μm. The obtained MOFs demonstrate the characteristic microporous network with a surface area of ∼1851 m2 g−1 and a pore volume of ∼0.78 cm3 g−1, which benefit to adsorb high quantity of CO2 ∼ 6.73 mol kg−1 at ordinary pressure. X-ray diffraction studies indicate that the MOFs possess an outstanding diffraction intensity ratio of the crystal plane (2, 2, 2) to (2, 0, 0), I(222)/I(200) = 22.4. The MSC method provides a cost-effective approach for large-scale production of MOFs with more attractive properties than others. Most importantly, it can significantly cut down the waste liquid and production cost
How Do South American International Students Experience Student Life in Flanders? A Photo Elicitation Project
Millions of tertiary international students are studying abroad, and the number of exchange students continues to increase. We explored experiences of South American students studying in a non-Anglophone context. A photo elicitation methodology was applied to support data collection. Five participants were asked to visualize their challenges in their adjustment in pictures. We conducted individual interviews where images were used as prompts to narratives. Data were analyzed using a thematic analysis approach. Three main themes were identified: socio-cultural adjustment, academic adjustment, and psychological adjustment. Our data suggest that adjustment processes do not automatically lead to an adaptation outcome. Individual factors such as students’ acculturation strategies and coping mechanisms, and situational variables like social interaction and cultural discomfort affect their adjustment
On the special oxidation mechanism of a Mg-Y-Al alloy contained LPSO phase at high temperatures
This work investigated the oxidation of Mg-11Y-1Al alloy in Ar-20%O2 at
500{\deg}through multiscale characterization. The results show that the
network-like long-period stacking ordered(LPSO) phase decomposed into a
needle-like LPSO phase and a polygonal Mg24Y5 phase. The needle-like LPSO phase
resulted in the formation of a high-dense of needle-like oxide at the oxidation
front of the area initially occupied by the network-like LPSO phase. The
further inward oxygen would diffuse along the needle-like oxide-matrix
interfaces and react with Y in the surrounding Mg matrix, resulting in the
lateral growth of these needle-like oxides. Finally, the discrete needle-like
oxides were interconnected to form a thicker and continuous oxide scale which
could be more effective in hindering the elemental diffusion. Meanwhile, Al
could partially enter the Y2O3 oxide scale and formed a strengthened (Y,Al)O
oxide scale which could show a greater resistance to cracking and debonding
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