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2. 90 degree Inclined Pulsar
- Abstract:
- Current sheet and open field lines with footpoints near the edge of the polar cap. The magnetic axis is inclined relative to the rotation axis by 90 degrees. Red field lines originate on the north polar cap and green field lines in the right panel originate on the south polar cap. Purple and grey colors indicate positive and negative net local charge density in the current sheet, which is shown between 1.2-2 light cylinder radii.
- Type:
- moving image
- Issue Date:
- 21 November 2013
3. A dual-mechanism antibiotic kills Gram-negative bacteria and avoids drug resistance
- Author(s):
- Martin, James K; Sheehan, Joseph P; Bratton, Benjamin P; Moore, Gabriel M; Mateus, André; Li, Sophia Hsin-Jung; Kim, Hahn; Rabinowitz, Joshua D; Typas, Athanasios; Savitski, Mikhail M; Wilson, Maxwell Z; Gitai, Zemer
- Abstract:
- The rise of antibiotic resistance and declining discovery of new antibiotics have created a global health crisis. Of particular concern, no new antibiotic classes have been approved for treating Gram-negative pathogens in decades. Here, we characterize a compound, SCH-79797, that kills both Gram-negative and Gram-positive bacteria through a unique dual-targeting mechanism of action (MoA) with undetectably-low resistance frequencies. To characterize its MoA, we combined quantitative imaging, proteomic, genetic, metabolomic, and cell-based assays. This pipeline demonstrates that SCH-79797 has two independent cellular targets, folate metabolism and bacterial membrane integrity, and outperforms combination treatments in killing MRSA persisters. Building on the molecular core of SCH-79797, we developed a derivative, Irresistin-16, with increased potency and showed its efficacy against Neisseria gonorrheae in a mouse vaginal infection model. This promising antibiotic lead suggests that combining multiple MoAs onto a single chemical scaffold may be an underappreciated approach to targeting challenging bacterial pathogens.
- Type:
- Dataset
- Issue Date:
- 20 May 2020
4. Accessing Real-Life Episodic Information from Minutes versus Hours Earlier Modulates Hippocampal and High-Order Cortical Dynamics
- Author(s):
- Chen, Janice; Honey, Christopher; Simony, Erez; Arcaro, Michael; Norman, Kenneth; Hasson, Uri
- Abstract:
- It is well known that formation of new episodic memories depends on hippocampus, but in real-life settings (e.g., conversation), hippocampal amnesics can utilize information from several minutes earlier. What neural systems outside hippocampus might support this minutes-long retention? In this study, subjects viewed an audiovisual movie continuously for 25 min; another group viewed the movie in 2 parts separated by a 1-day delay. Understanding Part 2 depended on retrieving information from Part 1, and thus hippocampus was required in the day-delay condition. But is hippocampus equally recruited to access the same information from minutes earlier? We show that accessing memories from a few minutes prior elicited less interaction between hippocampus and default mode network (DMN) cortical regions than accessing day-old memories of identical events, suggesting that recent information was available with less reliance on hippocampal retrieval. Moreover, the 2 groups evinced reliable but distinct DMN activity timecourses, reflecting differences in information carried in these regions when Part 1 was recent versus distant. The timecourses converged after 4 min, suggesting a time frame over which the continuous-viewing group may have relied less on hippocampal retrieval. We propose that cortical default mode regions can intrinsically retain real-life episodic information for several minutes.
- Type:
- Dataset
- Issue Date:
- 3 August 2015
5. Achromonodin-1 NMR spectra
- Author(s):
- Link, A. James; Carson, Drew V.; So, Larry; Cheung-Lee, Wai Ling
- Abstract:
- This entry encompasses the raw NMR spectra used to determine the structure of the lasso peptide achromonodin-1. Within one file are included the five following spectra: COSY, TOCSY, NOESY (150 ms mixing time), NOESY (700 ms mixing time), and C,H HSQC. The file requires Mestrenova software to read. These spectra were used to develop the 3D structure models of achromonodin-1 that are deposited at the protein data bank (PDB) as entry 8SVB.
- Type:
- Dataset
- Issue Date:
- June 2023
6. Aligned Nonspinning Dipoles
- Abstract:
- Magnetic field lines and current sheets for an orbiting neutron star binary with the magnetic moments of both stars aligned with the rotation axis. The stars are not spinning, i.e., R_{LC,∗} = ∞. Fields are by and large confined to the half of the magnetosphere closer to their source star. This movie shows the corotating field pattern as the orbit progresses.
- Type:
- moving image
- Issue Date:
- 21 November 2013
7. Aligned Rapidly Spinning Dipoles
- Abstract:
- Magnetic field lines and current sheets for an orbiting neutron star binary with the magnetic moments of both stars aligned with the rotation axis. The stars are spinning rapidly at ∼ ms periods, with R_{LC,∗}/R_∗ = 2.7. Stellar spin winds fields backwards toroidally, and they can propagate to the far side of the magnetosphere closer to the opposing star. This movie shows the corotating field pattern as the orbit progresses.
- Type:
- moving image
- Issue Date:
- 21 November 2013
8. Amplification of local changes along the timescale processing hierarchy
- Author(s):
- Yeshurun, Yaara; Nguyen, Mai; Hasson, Uri
- Abstract:
- Small changes in word choice can lead to dramatically different interpretations of narratives. How does the brain accumulate and integrate such local changes to construct unique neural representations for different stories? In this study we created two distinct narratives by changing only a few words in each sentence (e.g. “he” to “she” or “sobbing” to “laughing”) while preserving the grammatical structure across stories. We then measured changes in neural responses between the two stories. We found that the differences in neural responses between the two stories gradually increased along the hierarchy of processing timescales. For areas with short integration windows, such as early auditory cortex, the differences in neural responses between the two stories were relatively small. In contrast, in areas with the longest integration windows at the top of the hierarchy, such as the precuneus, temporal parietal junction, and medial frontal cortices, there were large differences in neural responses between stories. Furthermore, this gradual increase in neural difference between the stories was highly correlated with an area’s ability to integrate information over time. Amplification of neural differences did not occur when changes in words did not alter the interpretation of the story (e.g. “sobbing” to “crying”). Our results demonstrate how subtle differences in words are gradually accumulated and amplified along the cortical hierarchy as the brain constructs a narrative over time.
- Type:
- Dataset
- Issue Date:
- August 2017
9. An extended MHD study of the 16 October 2015 MMS diffusion region crossing
- Abstract:
- The Magnetospheric Multiscale (MMS) mission has given us unprecedented access to high cadence particle and field data of magnetic reconnection at Earth's magnetopause. MMS first passed very near an X-line on 16 October 2015, the Burch event, and has since observed multiple X-line crossings. Subsequent 3D particle-in-cell (PIC) modeling efforts of and comparison with the Burch event have revealed a host of novel physical insights concerning magnetic reconnection, turbulence induced particle mixing, and secondary instabilities. In this study, we employ the Gkeyll simulation framework to study the Burch event with different classes of extended, multi-fluid magnetohydrodynamics (MHD), including models that incorporate important kinetic effects, such as the electron pressure tensor, with physics-based closure relations designed to capture linear Landau damping. Such fluid modeling approaches are able to capture different levels of kinetic physics in global simulations and are generally less costly than fully kinetic PIC. We focus on the additional physics one can capture with increasing levels of fluid closure refinement via comparison with MMS data and existing PIC simulations. In particular, we find that the ten-moment model well captures the agyrotropic structure of the pressure tensor in the vicinity of the X-line and the magnitude of anisotropic electron heating observed in MMS and PIC simulations. However, the ten-moment model has difficulty resolving the lower hybrid drift instability, which has been observed to plays a fundamental role in heating and mixing electrons in the current layer.
- Type:
- Dataset
10. Antialigned Nonspinning Dipoles
- Abstract:
- Magnetic field lines and current sheets for an orbiting neutron star binary with the magnetic moment of one star aligned with the rotation axis, and the magnetic moment of the other star tilted and antialigned with the rotation axis. The stars are not spinning, i.e., R_{LC,∗} = ∞. Fields from each star encircle the other star and force fields coming off the second star backwards toroidally. This movie shows the corotating field pattern as the orbit progresses.
- Type:
- moving image
- Issue Date:
- 21 November 2013
11. Antialigned Rapidly Spinning Dipoles
- Abstract:
- Magnetic field lines and current sheets for an orbiting neutron star binary with the magnetic moment of one star aligned with the rotation axis, and the magnetic moment of the other star tilted and antialigned with the rotation axis. The stars are spinning rapidly at ∼ ms periods, with R_{LC,∗} /R_∗ = 2.7. Stellar spin winds fields backwards toroidally. This movie shows the corotating field pattern as the orbit progresses.
- Type:
- moving image
- Issue Date:
- 21 November 2013
12. Attentional Modulation of Brain Responses to Primary Appetitive and Aversive Stimuli
- Author(s):
- Cara L. Buck; Jonathan D. Cohen; Field, Brent; Daniel Kahneman; Samuel M. McClure; Leigh E. Nystrom
- Abstract:
- Studies of subjective well-being have conventionally relied upon self-report, which directs subjects’ attention to their emotional experiences. This method presumes that attention itself does not influence emotional processes, which could bias sampling. We tested whether attention influences experienced utility (the moment-by-moment experience of pleasure) by using functional magnetic resonance imaging (fMRI) to measure the activity of brain systems thought to represent hedonic value while manipulating attentional load. Subjects received appetitive or aversive solutions orally while alternatively executing a low or high attentional load task. Brain regions associated with hedonic processing, including the ventral striatum, showed a response to both juice and quinine. This response decreased during the high-load task relative to the low-load task. Thus, attentional allocation may influence experienced utility by modulating (either directly or indirectly) the activity of brain mechanisms thought to represent hedonic value.
- Type:
- Dataset, Software, and text
- Issue Date:
- 11 February 2015
13. CLEVR-Matrices
- Author(s):
- Mondal, Shanka Subhra; Webb, Taylor; Cohen, Jonathan
- Abstract:
- A dataset of Raven’s Progressive Matrices (RPM)-like problems using realistically rendered 3D shapes, based on source code from CLEVR (a popular visual-question-answering dataset) (Johnson, J., Hariharan, B., Van Der Maaten, L., Fei-Fei, L., Lawrence Zitnick, C., & Girshick, R. (2017). Clevr: A diagnostic dataset for compositional language and elementary visual reasoning. In Proceedings of the IEEE conference on computer vision and pattern recognition (pp. 2901-2910)).
- Type:
- Dataset
- Issue Date:
- 1 March 2023
14. Calcium responses to acoustic stimuli in Drosophila melanogaster
- Author(s):
- Baker, Christa
- Abstract:
- These files contain the calcium responses of Drosophila auditory neurons to acoustic stimuli.
- Type:
- Dataset
- Issue Date:
- 30 June 2022
15. Chiral Tetramer Molecular Model
- Author(s):
- Petsev, Nikolai D.; Stillinger, Frank H.; Debenedetti, Pablo G.
- Abstract:
- Source code for our energy-conserving reformulation of the 4-site molecular model for chiral phenomena originally introduced by Latinwo et al. [F. Latinwo, F. H. Stillinger, and P. G. Debenedetti, Molecular Model for Chirality Phenomena, J. Chem. Phys. 145, 154503 (2016)]. The reformulation includes an additional 8-body force that arises from an explicit configuration-dependent term in the potential energy function, resulting in a coarse-grained energy-conserving force field for molecular dynamics simulations of chirality phenomena. In this model, the coarse-grained interaction energy between two tetramers depends on their respective chiralities, and is controlled by a parameter λ, where favors local configurations involving tetramers of opposite chirality, and gives energetic preference to configurations involving tetramers of the same chirality. The source code is for use with the LAMMPS simulation package.
- Type:
- Software
- Issue Date:
- 3 August 2021
16. Climate Impacts from Large Volcanic Eruptions in a High-resolution Climate Model: the Importance of Forcing Structure
- Author(s):
- Yang, Wenchang; Vecchi, Gabriel; Fueglistaler, Stephan; Horowitz, Larry; Luet, David; Muñoz, Ángel; Paynter, David; Underwood, Seth
- Abstract:
- Explosive volcanic eruptions have large climate impacts, and can serve as observable tests of the climatic response to radiative forcing. Using a high resolution climate model, we contrast the climate responses to Pinatubo, with symmetric forcing, and those to Santa Maria and Agung, which had meridionally asymmetric forcing. Although Pinatubo had larger global-mean forcing, asymmetric forcing strongly shifts the latitude of tropical rainfall features, leading to larger local precipitation/TC changes. For example, North Atlantic TC activity over is enhanced/reduced by SH-forcing (Agung)/NH-forcing (Santa Maria), but changes little in response to the Pinatubo forcing. Moreover, the transient climate sensitivity estimated from the response to Santa Maria is 20% larger than that from Pinatubo or Agung. This spread in climatic impacts of volcanoes needs to be considered when evaluating the role of volcanoes in global and regional climate, and serves to contextualize the well-observed response to Pinatubo.
- Type:
- Dataset
- Issue Date:
- 2019
17. Code and data from "Comparative genomic analysis reveals varying levels of mammalian adaptation to coronavirus infections"
- Author(s):
- King, Sean
- Abstract:
- Severe acute respiratory coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, is of zoonotic origin. Evolutionary analyses assessing whether coronaviruses similar to SARS-CoV-2 infected ancestral species of modern-day animal hosts could be useful in identifying additional reservoirs of potentially dangerous coronaviruses. We reasoned that if a clade of species has been repeatedly exposed to a virus, then their proteins relevant for viral entry may exhibit adaptations that affect host susceptibility or response. We perform comparative analyses across the mammalian phylogeny of angiotensin-converting enzyme 2 (ACE2), the cellular receptor for SARS-CoV-2, in order to uncover evidence for selection acting at its binding interface with the SARS-CoV-2 spike protein. We uncover that in rodents there is evidence for adaptive amino acid substitutions at positions comprising the ACE2-spike interaction interface, whereas the variation within ACE2 proteins in primates and some other mammalian clades is not consistent with evolutionary adaptations. We also analyze aminopeptidase N (APN), the receptor for the human coronavirus 229E, a virus that causes the common cold, and find evidence for adaptation in primates. Altogether, our results suggest that the rodent and primate lineages may have had ancient exposures to viruses similar to SARS-CoV-2 and HCoV-229E, respectively. Included in this repository are the instructions and corresponding code required to build the dataset and run the analysis in the manuscript.
- Type:
- Dataset
- Issue Date:
- 28 September 2021
18. Complementary learning systems within the hippocampus: A neural network modeling approach to reconciling episodic memory with statistical learning
- Author(s):
- Schapiro, Anna; Turk-Browne, Nicholas; Botvinick, Matthew; Norman, Kenneth
- Type:
- interactive resource
- Issue Date:
- 2016
19. CrvA and CrvB form a curvature-inducing module sufficient to induce cell shape complexity in Gram-negative bacteria
- Author(s):
- Martin, Nicholas R; Blackman, Edith; Bratton, Benjamin P; Chase, Katelyn J; Bartlett, Thomas M; Gitai, Zemer
- Abstract:
- Bacterial species have diverse cell shapes that enable motility, colonization, and virulence. The cell wall defines bacterial shape and is primarily built by two cytoskeleton-guided synthesis machines, the elongasome and the divisome. However, the mechanisms producing complex shapes, like the curved-rod shape of Vibrio cholerae, are incompletely defined. Previous studies have reported that species-specific regulation of cytoskeleton-guided machines enables formation of complex bacterial shapes such as cell curvature and cellular appendages. In contrast, we report that CrvA and CrvB are sufficient to induce complex cell shape autonomously of the cytoskeleton in V. cholerae. The autonomy of the CrvAB module also enables it to induce curvature in the Gram-negative species Escherichia coli, Pseudomonas aeruginosa, Caulobacter crescentus, and Agrobacterium tumefaciens. Using inducible gene expression, quantitative microscopy, and biochemistry we show that CrvA and CrvB circumvent the need for patterning via cytoskeletal elements by regulating each other to form an asymmetrically-localized, periplasmic structure that directly binds to the cell wall. The assembly and disassembly of this periplasmic structure enables dynamic changes in cell shape. Bioinformatics indicate that CrvA and CrvB may have diverged from a single ancestral hybrid protein. Using fusion experiments in V. cholerae, we find that a synthetic CrvA/B hybrid protein is sufficient to induce curvature on its own, but that expression of two distinct proteins, CrvA and CrvB, promotes more rapid curvature induction. We conclude that morphological complexity can arise independently of cell shape specification by the core cytoskeleton-guided synthesis machines.
- Type:
- Dataset
- Issue Date:
- 2021
20. Data Files for "Arranged Cohabitation among Chinese Muslims"
- Author(s):
- Yu, Xie; Qing, Lai; Zheng, Mu
- Abstract:
- Data from the 2007 Developmental Idealism survey conducted in Gansu province in China's northwestern borderlands reveal that Muslims of the Hui and Dongxiang ethnicities reported much higher rates of cohabitation experience than the secular majority Han. Based on follow-up qualitative interviews, we found the answer to lie in the interplay between the highly interventionist Chinese state and the robust cultural resilience of local Islamic communities. Using the 2000 census data and the 2010 China Family Panel Studies data, we further show that women in almost all ten Muslim ethnic groups have higher percentages of underage births and premarital births than Han women, both nationally and in the northwest where most Chinese Muslims live. As the once-outlawed behavior of cohabitation became more socially acceptable during the reform and opening-up era, young Muslim Chinese often found themselves in “arranged cohabitations” as de facto marriages formed at younger-than-legal ages.
- Type:
- Dataset
- Issue Date:
- January 2024
