59,369 research outputs found
On the influence of social bots in online protests. Preliminary findings of a Mexican case study
Social bots can affect online communication among humans. We study this
phenomenon by focusing on #YaMeCanse, the most active protest hashtag in the
history of Twitter in Mexico. Accounts using the hashtag are classified using
the BotOrNot bot detection tool. Our preliminary analysis suggests that bots
played a critical role in disrupting online communication about the protest
movement.Comment: 10 page
BoostNet: Bootstrapping detection of socialbots, and a case study from Guatemala
We present a method to reconstruct networks of socialbots given minimal
input. Then we use Kernel Density Estimates of Botometer scores from 47,000
social networking accounts to find clusters of automated accounts, discovering
over 5,000 socialbots. This statistical and data driven approach allows for
inference of thresholds for socialbot detection, as illustrated in a case study
we present from Guatemala.Comment: 7 pages, 4 figure
Recommended from our members
Functional and mutational analysis of the light-harvesting chlorophyll a/b protein of thylakoid membranes.
The precursor for a Lemna light-harvesting chlorophyll a/b protein (pLHCP) has been synthesized in vitro from a single member of the nuclear LHCP multigene family. We report the sequence of this gene. When incubated with Lemna chloroplasts, the pLHCP is imported and processed into several polypeptides, and the mature form is assembled into the light-harvesting complex of photosystem II (LHC II). The accumulation of the processed LHCP is enhanced by the addition to the chloroplasts of a precursor and a co-factor for chlorophyll biosynthesis. Using a model for the arrangement of the mature polypeptide in the thylakoid membrane as a guide, we have created mutations that lie within the mature coding region. We have studied the processing, the integration into thylakoid membranes, and the assembly into light-harvesting complexes of six of these deletions. Four different mutant LHCPs are found as processed proteins in the thylakoid membrane, but only one appears to have an orientation in the membrane that is similar to that of the wild type. No mutant LHCP appears in LHC II. The other two mutant LHCPs cannot be detected within the chloroplasts. We conclude that stable complex formation is not required for the processing and insertion of altered LHCPs into the thylakoid membrane. We discuss the results in light of our model
Assembly of the precursor and processed light-harvesting chlorophyll a/b protein of Lemna into the light-harvesting complex II of barley etiochloroplasts.
When the in vitro synthesized precursor of a light-harvesting chlorophyll a/b binding protein (LHCP) from Lemna gibba is imported into barley etiochloroplasts, it is processed to a single form. Both the processed form and the precursor are found in the thylakoid membranes, assembled into the light-harvesting complex of photosystem II. Neither form can be detected in the stromal fraction. The relative amounts of precursor and processed forms observed in the thylakoids are dependent on the developmental stage of the plastids used for uptake. The precursor as well as the processed form can also be detected in thylakoids of greening maize plastids used in similar uptake experiments. This detection of a precursor in the thylakoids, which has not been previously reported, could be a result of using rapidly developing plastids and/or using an heterologous system. Our results demonstrate that the extent of processing of LHCP precursor is not a prerequisite for its inclusion in the complex. They are also consistent with the possibility that the processing step can occur after insertion of the protein into the thylakoid membrane
Nanofiller-tuned microporous polymer molecular sieves for energy and environmental processes
10.1039/c5ta09060aJournal of Materials Chemistry A41270-27
- …