Growing transverse oscillations of a multistranded loop observed by SDO/AIA

The first evidence of transverse oscillations of a multistranded loop with growing amplitudes and internal coupling observed by the Atomspheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO) is presented. The loop oscillation event occurred on 2011 March 8, triggered by a CME. The multiwavelength analysis reveals the presence of multithermal strands in the oscillating loop, whose dynamic behaviors are temperature-dependent, showing differences in their oscillation amplitudes, phases and emission evolution. The physical parameters of growing oscillations of two strands in 171 A are measured and the 3-D loop geometry is determined using STEREO-A/EUVI data. These strands have very similar frequencies, and between two 193 A strands a quarter-period phase delay sets up. These features suggest the coupling between kink oscillations of neighboring strands and the interpretation by the collective kink mode as predicted by some models. However, the temperature dependence of the multistarnded loop oscillations was not studied previously and needs further investigation. The transverse loop oscillations are associated with intensity and loop width variations. We suggest that the amplitude-growing kink oscillations may be a result of continuous non-periodic driving by magnetic deformation of the CME, which deposits energy into the loop system at a rate faster than its loss.Comment: 6 pages, 4 color figures, 1 table, ApJ Letter, accepte

Functional Studies of CCAAT/Enhancer Binding Protein Site Located Downstream of the Transcriptional Start Site.

Previous studies have identified a CCAAT/enhancer binding protein (C/EBP) site located downstream of the transcriptional start site (DS3). The role of the DS3 element with respect to HIV-1 transactivation by Tat and viral replication has not been characterized. We have demonstrated that DS3 was a functional C/EBPβ binding site and mutation of this site to the C/EBP knockout DS3-9C variant showed lower HIV-1 long terminal repeat (LTR) transactivation by C/EBPβ. However, it was able to exhibit similar or even higher transcription levels by Tat compared to the parental LTR. C/EBPβ and Tat together further enhanced the transcription level of the parental LAI-LTR and DS3-9C LTR, with higher levels in the DS3-9C LTR. HIV molecular clone viruses carrying the DS3-9C variant LTR demonstrated a decreased replication capacity and delayed rate of replication. These results suggest that DS3 plays a role in virus transcriptional initiation and provides new insight into C/EBP regulation of HIV-1

Transverse-Earthquake Induced Deformations of a Bridge Approach Embankment in the New Madrid Seismic Zone

It is predicted that strong earthquakes, larger than M 7.0, may occur within next 50 years in the New Madrid Seismic Zone (NMSZ), the location of three of the most powerful earthquakes in United States history. Large displacements may occur during strong earthquakes that can cause an embankment to fail or lose its function. The hyperbolic stress-strain model with Masing rules was modified to account for strength and stiffness reduction due to change in the effective confining pressure. The Byrne model was combined with a hyperbolic model to calculate the pore water pressure caused by seismic shaking. This modified hyperbolic model was implemented into the computer code, FLAC, and calibrated against the 1971 Upper San Fernando Dam failure. It appears that the modified model is superior to the built-in Finn model in FLAC to predict the earthquake-induced deformation of the embankments. Then it was applied to study the seismically induced deformation of an approach embankment to Bridge A1466 in the NMSZ near Hayti, Missouri

Predicting the Transportation Activities of Construction Waste Hauling Trucks: An Input-Output Hidden Markov Approach

Construction waste hauling trucks (CWHTs), as one of the most commonly seen heavy-duty vehicles in major cities around the globe, are usually subject to a series of regulations and spatial-temporal access restrictions because they not only produce significant NOx and PM emissions but also causes on-road fugitive dust. The timely and accurate prediction of CWHTs' destinations and dwell times play a key role in effective environmental management. To address this challenge, we propose a prediction method based on an interpretable activity-based model, input-output hidden Markov model (IOHMM), and validate it on 300 CWHTs in Chengdu, China. Contextual factors are considered in the model to improve its prediction power. Results show that the IOHMM outperforms several baseline models, including Markov chains, linear regression, and long short-term memory. Factors influencing the predictability of CWHTs' transportation activities are also explored using linear regression models. Results suggest the proposed model holds promise in assisting authorities by predicting the upcoming transportation activities of CWHTs and administering intervention in a timely and effective manner.Comment: 21 pages, 8 figure

The Transcription Factors ADR1 or CAT8 are Required for RTG Pathway Activation and Evasion from Yeast Acetic Acid-Induced Programmed Cell Death in Raffinose

Yeast Saccharomyces cerevisiae grown on glucose undergoes programmed cell death (PCD) induced by acetic acid (AA-PCD), but evades PCD when grown in raffinose. This is due to concomitant relief of carbon catabolite repression (CCR) and activation of mitochondrial retrograde signaling, a mitochondria-to-nucleus communication pathway causing up-regulation of various nuclear target genes, such as CIT2, encoding peroxisomal citrate synthase, dependent on the positive regulator RTG2 in response to mitochondrial dysfunction. CCR down-regulates genes mainly involved in mitochondrial respiratory metabolism. In this work, we investigated the relationships between the RTG and CCR pathways in the modulation of AA-PCD sensitivity under glucose repression or de-repression conditions. Yeast single and double mutants lacking RTG2 and/or certain factors regulating carbon source utilization, including MIG1, HXK2, ADR1, CAT8, and HAP4, have been analyzed for their survival and CIT2 expression after acetic acid treatment. ADR1 and CAT8 were identified as positive regulators of RTG-dependent gene transcription. ADR1 and CAT8 interact with RTG2 and with each other in inducing cell resistance to AA-PCD in raffinose and controlling the nature of cell death. In the absence of ADR1 and CAT8, AA-PCD evasion is acquired through activation of an alternative factor/pathway repressed by RTG2, suggesting that RTG2 may play a function in promoting necrotic cell death in repressing conditions when RTG pathway is inactive. Moreover, our data show that simultaneous mitochondrial retrograde pathway activation and SNF1-dependent relief of CCR have a key role in central carbon metabolism reprogramming which modulates the yeast acetic acid-stress response

Head-to-Tail: How Knowledgeable are Large Language Models (LLM)? A.K.A. Will LLMs Replace Knowledge Graphs?

Since the recent prosperity of Large Language Models (LLMs), there have been interleaved discussions regarding how to reduce hallucinations from LLM responses, how to increase the factuality of LLMs, and whether Knowledge Graphs (KGs), which store the world knowledge in a symbolic form, will be replaced with LLMs. In this paper, we try to answer these questions from a new angle: How knowledgeable are LLMs? To answer this question, we constructed Head-to-Tail, a benchmark that consists of 18K question-answer (QA) pairs regarding head, torso, and tail facts in terms of popularity. We designed an automated evaluation method and a set of metrics that closely approximate the knowledge an LLM confidently internalizes. Through a comprehensive evaluation of 14 publicly available LLMs, we show that existing LLMs are still far from being perfect in terms of their grasp of factual knowledge, especially for facts of torso-to-tail entities

SDO/AIA Detection of Solar Prominence Formation within a Coronal Cavity

We report the first analyses of SDO/AIA observations of the formation of a quiescent polar crown prominence in a coronal cavity. The He II 304 \AA\ (log T_{max} ~ 4.8 K) data show both the gradual disappearance of the prominence due to vertical drainage and lateral transport of plasma followed by the formation of a new prominence some 12 hours later. The formation of the prominence is preceded by the appearance of a bright emission "cloud" in the central region of the coronal cavity. The peak brightness of the cloud progressively shifts in time from the Fe XIV 211 \AA\ channel, through the Fe XII 193 \AA\ channel, to the Fe IX 171 \AA\ channel (log T_{max} ~ 6.2, 6.1, 5.8 K, respectively) while simultaneously decreasing in altitude. Filter ratio analysis estimates the initial temperature of the cloud in the cavity to be approximately log T \sim 6.25 K with evidence of cooling over time. The subsequent growth of the prominence is accompanied by darkening of the cavity in the 211 \AA\ channel. The observations imply the possibility of prominence formation via in situ condensation of hot plasma from the coronal cavity, in support of the proposed process of magneto-thermal convection in coronal magnetic flux ropes.Comment: 7 pages, 5 figures, accepted by The Astrophysical Journal Letter

Noninvasive Transcranial Focal Stimulation Via Tripolar Concentric Ring Electrodes Lessens Behavioral Seizure Activity of Recurrent Pentylenetetrazole Administrations in Rats

Epilepsy affects approximately 1% of the world population. Antiepileptic drugs are ineffective in approximately 30% of patients and have side effects. We have been developing a noninvasive transcranial focal electrical stimulation with our novel tripolar concentric ring electrodes as an alternative/complementary therapy for seizure control. In this study we demonstrate the effect of focal stimulation on behavioral seizure activity induced by two successive pentylenetetrazole administrations in rats. Seizure onset latency, time of the first behavioral change, duration of seizure, and maximal seizure severity score were studied and compared for focal stimulation treated (n = 9) and control groups (n = 10). First, we demonstrate that no significant difference was found in behavioral activity for focal stimulation treated and control groups after the first pentylenetetrazole administration. Next, comparing first and second pentylenetetrazole administrations, we demonstrate there was a significant change in behavioral activity (time of the first behavioral change) in both groups that was not related to focal stimulation. Finally, we demonstrate focal stimulation provoking a significant change in seizure onset latency, duration of seizure, and maximal seizure severity score. We believe that these results, combined with our previous reports, suggest that transcranial focal stimulation may have an anticonvulsant effect