2,641 research outputs found
Studying the Structure of Terrorist Networks: A Web Structural Mining Approach
Because terrorist organizations often operate in network forms where individual terrorists collaborate with each other to carry out attacks, we could gain valuable knowledge about the terrorist organizations by studying structural properties of such terrorist networks. However, previous studies of terrorist network structure have generated little actionable results. This is due to the difficulty in collecting and accessing reliable data and the lack of advanced network analysis methodologies in the field. To address these problems, we introduced the Web structural mining technique into the terrorist network analysis field which, to the best our knowledge, has never been done before. We employed the proposed technique on a Global Salafi Jihad network dataset collected through a large scale empirical study. Results from our analysis not only provide insights for terrorism research community but also support decision making in law-reinforcement, intelligence, and security domains to make our nation safer
Alternative Use of DNA Binding Domains by the Neurospora White Collar Complex Dictates Circadian Regulation and Light Responses
In the Neurospora circadian system, the White Collar complex (WCC) of WC-1 and WC-2 drives transcription of the circadian pacemaker gene frequency (frq), whose gene product, FRQ, as a part of the FRQ-FRH complex (FFC), inhibits its own expression. The WCC is also the principal Neurospora photoreceptor; WCC-mediated light induction of frq resets the clock, and all acute light induction is triggered by WCC binding to promoters of light-induced genes. However, not all acutely light-induced genes are also clock regulated, and conversely, not all clock-regulated direct targets of WCC are light induced; the structural determinants governing the shift from WCC\u27s dark circadian role to its light activation role are poorly described. We report that the DBD region (named for being defective in binding DNA), a basic region in WC-1 proximal to the DNA-binding zinc finger (ZnF) whose function was previously ascribed to nuclear localization, instead plays multiple essential roles assisting in DNA binding and mediating interactions with the FFC. DNA binding for light induction by the WCC requires only WC-2, whereas DNA binding for circadian functions requires WC-2 as well as the ZnF and DBD motif of WC-1. The data suggest a means by which alterations in the tertiary and quaternary structures of the WCC can lead to its distinct functions in the dark and in the light
Conjugation site heterogeneity causes variable electrostatic properties in Fc conjugates
Immunoconjugates, including antibody-drug conjugates and Fc-conjugates, represent a rapidly growing class of therapeutics undergoing clinical development. Despite their growing popularity, the high intrinsic heterogeneity of immunoconjugates often complicates the development process and limits their widespread application. In particular, immunoconjugate charge variants exhibit markedly different colloidal stabilities, solubilities, pharmacokinetics and tissue distributions. Charge variants arise spontaneously due to degradation and, depending on the type of drug, linker and conjugation site, through drug conjugation. Electrostatic changes in naked antibodies often result in poor performance characteristics, and therefore charge alterations due to degradation are critical to control. Charge properties are expected to be equally important to producing well-behaved ADCs. Charge-based methods of analysis, such as isoelectric focusing and ion exchange chromatography, are capable of probing the underlying complexities within immunoconjugate drug products. Despite the utility of these methods, there are only a few published reports of charge-based assays applied to immunoconjugates. In the present study, we sought to identify the effects of chemical conjugation on the electrostatic properties of Fc-conjugates. In order to minimize the effects of post-translational modifications (e.g. deamidation), a single Fc charge variant was isolated prior to conjugation of a fluorescent probe, Alexa Fluor 350, to the side chains of lysine residues. The resulting Fc-conjugates were assessed by a variety of analytical techniques, including isoelectric focusing and ion exchange chromatography, to determine their charge properties
Quantitative Genetic Mapping and Genome Assembly in the Lesser Wax Moth Achroia grisella
This work is licensed under a Creative Commons Attribution 4.0 International License.Specific characteristics of the male Achroia grisella acoustic mating signal determine a male’s attractiveness toward females. These features are genetically variable in populations, and mapping experiments have been used to identify loci contributing to song variation, and understand the evolutionary forces acting on this important sexual trait. Here we built on this foundation and carried out QTL (Quantitative Trait Locus) mapping using >1,000 recombinant individuals, genotyping this large cohort at thousands of sequence-based markers covering the entire collection of 30 A. grisella chromosomes. This dense marker set, coupled with our development of an annotated, draft genome of A. grisella, allowed us to link >3,000 genome scaffolds, >10,000 predicted genes, and close to 275Mb of genome sequence to chromosomes. Our QTL mapping confirmed a fraction of the QTL identified in a previous study, and additionally revealed novel loci. Collectively, QTL explained only small fractions of the phenotypic variance, suggesting many more causative factors remain below the detection threshold of our study. A surprising, and ultimately challenging feature of our study was the low level of intrachromosomal recombination present in our mapping population. This led to difficulty ordering markers along linkage groups, necessitating a chromosome-by-chromosome mapping approach, rather than true interval mapping, and precluded confident ordering/orienting of scaffolds along each chromosome. Nonetheless, our study increased the genomic resources available for the A. grisella system. Enabled by ever more powerful technologies, future investigators will be able to leverage our data to provide more detailed genetic dissection of male song variation in A. grisella.NSF IOB-0516634NIGMS award P20GM103638NIGMS award P20GM103418NIH R01 GM085260NIH R01 OD01097
Large-scale synthesis of Notum inhibitor 1-(2,4-dichloro-3-(trifluoromethyl)-phenyl)-1H-1,2,3-triazole (ARUK3001185) employing a modified Sakai reaction as the key step
1-Phenyl-1H-1,2,3-triazole 1 was prepared on large scale from aniline 4 by application of a one-pot Sakai–Clark reaction in good efficiency and high purity
A novel dimethylformamide (DMF) free bar-cast method to deposit organolead perovskite thin films with improved stability
We report a solvent-free approach to synthesizing organolead
perovskites by using solid state reactions to coat perovskite crystals
onto Al2O3 or TiO2 nanoparticles followed by addition of terpineol
affording perovskite inks. We have bar cast these inks to produce
photoactive perovskite thin films which are significantly more
stable to humidity than solution-processed films. This new method
also avoids the use of toxic DMF solvent
DNA replication is the target for the antibacterial effects of nonsteroidal anti-inflammatory drugs
Evidence suggests that some nonsteroidal anti-inflammatory drugs (NSAIDs) possess antibacterial properties with an unknown mechanism. We describe the in vitro antibacterial properties of the NSAIDs carprofen, bromfenac, and vedaprofen, and show that these NSAIDs inhibit the Escherichia coli DNA polymerase III β subunit, an essential interaction hub that acts as a mobile tether on DNA for many essential partner proteins in DNA replication and repair. Crystal structures show that the three NSAIDs bind to the sliding clamp at a common binding site required for partner binding. Inhibition of interaction of the clamp loader and/or the replicative polymerase α subunit with the sliding clamp is demonstrated using an in vitro DNA replication assay. NSAIDs thus present promising lead scaffolds for novel antibacterial agents targeting the sliding clamp
Bisphenol A and Its Analogues Activate Human Pregnane X Receptor
Background: Bisphenol A (BPA) is a base chemical used extensively in many consumer products. BPA and its analogues are present in environmental and human samples. Many endocrine-disrupting chemicals, including BPA, have been shown to activate the pregnane X receptor (PXR), a nuclear receptor that functions as a master regulator of xenobiotic metabolism. However, the detailed mechanism by which these chemicals activate PXR remains unknown
Neural correlates of suspiciousness and interactions with anxiety during emotional and neutral word processing
Suspiciousness is usually classified as a symptom of psychosis, but it also occurs in depression and anxiety disorders. Though how suspiciousness overlaps with depression is not obvious, suspiciousness does seem to overlap with anxious apprehension and anxious arousal (e.g., verbal iterative processes and vigilance about environmental threat). However, suspiciousness also has unique characteristics (e.g., concern about harm from others and vigilance about social threat). Given that both anxiety and suspiciousness have been associated with abnormalities in emotion processing, it is unclear whether it is the unique characteristics of suspiciousness or the overlap with anxiety that drive abnormalities in emotion processing. Event-related brain potentials were obtained during an emotion-word Stroop task. Results indicated that suspiciousness interacts with anxious apprehension to modulate initial stimulus perception processes. Suspiciousness is associated with attention to all stimuli regardless of emotion content. In contrast, anxious arousal is associated with a later response to emotion stimuli only. These results suggest that suspiciousness and anxious apprehension share overlapping processes, but suspiciousness alone is associated with a hyperactive early vigilance response. Depression did not interact with suspiciousness to predict response to emotion stimuli. These findings suggest that it may be informative to assess suspiciousness in conjunction with anxiety in order to better understand how these symptoms interact and contribute to dysfunctional emotion processing
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