Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Post-liquefaction reconsolidation of sand.

ABSTRACT: Loosely packed sand that is saturated with water can liquefy during an earthquake, potentially causing significant damage. Once the shaking is over, the excess pore water pressures that developed during the earthquake gradually dissipate, while the surface of the soil settles, in a process called post-liquefaction reconsolidation. When examining reconsolidation, the soil is typically divided in liquefied and solidified parts, which are modelled separately. The aim of this paper is to show that this fragmentation is not necessary. By assuming that the hydraulic conductivity and the one-dimensional stiffness of liquefied sand have real, positive values, the equation of consolidation can be numerically solved throughout a reconsolidating layer. Predictions made in this manner show good agreement with geotechnical centrifuge experiments. It is shown that the variation of one-dimensional stiffness with effective stress and void ratio is the most crucial parameter in accurately capturing reconsolidation.

SUBMITTER: Adamidis O

PROVIDER: S-EPMC4841662 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Post-liquefaction reconsolidation of sand.

Adamidis O O Madabhushi G S P GS

Proceedings. Mathematical, physical, and engineering sciences 20160201 2186

Loosely packed sand that is saturated with water can liquefy during an earthquake, potentially causing significant damage. Once the shaking is over, the excess pore water pressures that developed during the earthquake gradually dissipate, while the surface of the soil settles, in a process called post-liquefaction reconsolidation. When examining reconsolidation, the soil is typically divided in liquefied and solidified parts, which are modelled separately. The aim of this paper is to show that t ...[more]

PMID: 27118898

Similar Datasets

Influence of early stress on memory reconsolidation: Implications for post-traumatic stress disorder treatment.

Project description:Post-traumatic stress disorder (PTSD) is a common consequence of exposure to a life-threatening event. Currently, pharmacological treatments are limited by high rates of relapse, and novel treatment approaches are needed. We have recently demonstrated that propranolol, a ?-adrenergic antagonist, inhibited aversive memory reconsolidation in animals. Following this, in an open-label study 70% of patients with PTSD treated with propranolol during reactivation of traumatic memory exhibited full remission. However, the reason why 30% of these patients did not respond positively to propranolol treatment is still unclear. One of the major candidates as factor of treatment resistance is the patient's early-life traumatic history. To test the role of this factor, mice with pre- or postnatal stress are being tested in fear conditioning and in a new behavioral task, the "city-like", specifically designed as a mouse model of PTSD. After reactivation of the traumatic event, mice received propranolol injection to block the noradrenergic system during memory reconsolidation. Results show that, in the "city-like" test, control mice strongly avoided the shock compartment but also the compartments containing cues associated with the electric shocks. Injection of propranolol after reactivation greatly reduced the memory of the traumatic event, but this effect was not present when mice had received pre- or postnatal stress. Moreover, propranolol produced only a very weak effect in the fear conditioning test, and never changed the corticosterone level whatever the behavioral experiment. Taken together our results suggest that our new behavioural paradigm is well adapted to PTSD study in mice, and that early stress exposure may have an impact on propranolol PTSD treatment outcome. These data are critical to understanding the effect of propranolol treatment, in order to improve the therapeutic protocol currently used in humans.

| S-EPMC5774817 | biostudies-literature

Post Hoc Analysis of Passive Cavitation Imaging for Classification of Histotripsy-Induced Liquefaction in Vitro.

Project description:Histotripsy utilizes focused ultrasound to generate bubble clouds for transcutaneous tissue liquefaction. Bubble activity maps are under development to provide image guidance and monitor treatment progress. The aim of this paper was to investigate the feasibility of using plane wave B-mode and passive cavitation images to be used as binary classifiers of histotripsy-induced liquefaction. Prostate tissue phantoms were exposed to histotripsy pulses over a range of pulse durations (5- ) and peak negative pressures (12-23 MPa). Acoustic emissions were recorded during the insonation and beamformed to form passive cavitation images. Plane wave B-mode images were acquired following the insonation to detect the hyperechoic bubble cloud. Phantom samples were sectioned and stained to delineate the liquefaction zone. Correlation between passive cavitation and plane wave B-mode images and the liquefaction zone was assessed using receiver operating characteristic (ROC) curve analysis. Liquefaction of the phantom was observed for all the insonation conditions. The area under the ROC (0.94 versus 0.82), accuracy (0.90 versus 0.83), and sensitivity (0.81 versus 0.49) was greater for passive cavitation images relative to B-mode images ( ) along the azimuth of the liquefaction zone. The specificity was greater than 0.9 for both imaging modalities. These results demonstrate a stronger correlation between histotripsy-induced liquefaction and passive cavitation imaging compared with the plane wave B-mode imaging, albeit with limited passive cavitation image range resolution.

| S-EPMC5816682 | biostudies-other

Quantifying the Infectiousness of Post-Kala-Azar Dermal Leishmaniasis Toward Sand Flies.

Project description:BackgroundOn the Indian subcontinent, visceral leishmaniasis (VL) incidence is on track to reach elimination goals by 2020 in nearly all endemic districts. Although not included in official targets, previous data suggest post-kala-azar dermal leishmaniasis (PKDL) patients can act as an infection reservoir.MethodsWe conducted xenodiagnosis on 47 PKDL patients and 15 VL patients using laboratory-reared Phlebotomus argentipes. In direct xenodiagnosis, flies were allowed to feed on the patient's skin for 15 minutes. For indirect xenodiagnosis, flies were fed through a membrane on the patient's blood. Five days later, blood-fed flies were dissected and examined by microscopy and/or polymerase chain reaction (PCR). A 3-mm skin snip biopsy (PKDL) or venous blood (VL) was processed by quantitative PCR.ResultsTwenty-seven PKDL patients (57.4%) had positive results by direct and/or indirect xenodiagnosis. Direct was significantly more sensitive than indirect xenodiagnosis (55.3% vs 6.4%, P < .0001). Those with positive xenodiagnosis had median skin parasite loads >1 log10 unit higher than those with negative results (2.88 vs 1.66, P < .0001). In a multivariable model, parasite load, nodular lesions, and positive skin microscopy were significantly associated with positive xenodiagnosis. Blood parasite load was the strongest predictor for VL. Compared to VL, nodular PKDL was more likely and macular PKDL less likely to result in positive xenodiagnosis, but neither difference reached statistical significance.ConclusionsNodular and macular PKDL, and VL, can be infectious to sand flies. Active PKDL case detection and prompt treatment should be instituted and maintained as an integral part of VL control and elimination programs.

| S-EPMC6603265 | biostudies-literature

On-chip stool liquefaction via acoustofluidics.

Project description:Microfluidic-based portable devices for stool analysis are important for detecting established biomarkers for gastrointestinal disorders and understanding the relationship between gut microbiota imbalances and various health conditions, ranging from digestive disorders to neurodegenerative diseases. However, the challenge of processing stool samples in microfluidic devices hinders the development of a standalone platform. Here, we present the first microfluidic chip that can liquefy stool samples via acoustic streaming. With an acoustic transducer actively generating strong micro-vortex streaming, stool samples and buffers in microchannel can be homogenized at a flow rate up to 30 ?L min-1. After homogenization, an array of 100 ?m wide micropillars can further purify stool samples by filtering out large debris. A favorable biocompatibility was also demonstrated for our acoustofluidic-based stool liquefaction chip by examining bacteria morphology and viability. Moreover, stool samples with different consistencies were liquefied. Our acoustofluidic chip offers a miniaturized, robust, and biocompatible solution for stool sample preparation in a microfluidic environment and can be potentially integrated with stool analysis units for designing portable stool diagnostics platforms.

| S-EPMC6626638 | biostudies-literature

Alcohol-specific transcriptional dynamics of memory reconsolidation

Project description:To assess gene expression underlying alcohol memory in different regions of the brain, we performed total RNA-sequencing (RNA-seq) on brain tissue (prefrontal cortex or dorsal hippocampus) from C57BL/6 adult mice that had undergone alcohol placement conditioning and either placed back into alcohol context (retrieval, Ret) or briefly handled as a control (no retrieval, NoRet)

2023-03-07 | GSE205586 | GEO

Behavioral tagging underlies memory reconsolidation.

Project description:Memory reconsolidation occurs when a retrieving event destabilizes transiently a consolidated memory, triggering thereby a new process of restabilization that ensures memory persistence. Although this phenomenon has received wide attention, the effect of new information cooccurring with the reconsolidation process has been less explored. Here we demonstrate that a memory-retrieving event sets a neural tag, which enables the reconsolidation of memory after binding proteins provided by the original or a different contiguous experience. We characterized the specific temporal window during which this association is effective and identified the protein kinase A (PKA) and the extracellular signal-regulated kinase 1 and 2 (ERK 1/2) pathways as the mechanisms related to the setting of the reconsolidation tag and the synthesis of proteins. Our results show, therefore, that memory reconsolidation is mediated by a "behavioral tagging" process, which is common to different memory forms. They represent a significant advance in understanding the fate of memories reconsolidated while being adjacent to other events, and provide a tool for designing noninvasive strategies to attenuate (pathological/traumatic) or improve (education-related) memories.

| S-EPMC7395446 | biostudies-literature

Dataset on SPT-based seismic soil liquefaction.

Project description:This data article provides a summary of seismic soil liquefaction triggering and non-triggering case histories, which were compiled, screened for data completeness and quality, and then processed for the development of triggering relationships proposed in "SPT-based probabilistic and deterministic assessment of seismic soil liquefaction triggering hazard" [1]. The database is composed of 113 liquefaction, 95 non-liquefaction, and 2 marginal liquefaction case histories, from seismic events with moment magnitude Mw values varying in the range of 5.9 to 8.3. A spreadsheet summary of these case histories are included along with a separate spreadsheet, by which maximum likelihood assessment was performed. These data transparently enable researchers to access case history input parameters and processing details, and to compare the case history processing protocols with the ones of different researchers (e.g.: "The influence of SPT procedures in soil liquefaction resistance evaluations." [2], "SPT-based liquefaction triggering procedures." [3]).

| S-EPMC6126194 | biostudies-literature

Liquefaction and Rupture of Angiomyolipoma after Embolization.

Project description: Not available

| S-EPMC7710590 | biostudies-literature

Datasets for gravelly soil liquefaction case histories.

Project description:This data article provides summarized information on the liquefaction case histories of gravelly soil from 17 earthquakes. 234 historical cases based on the shear wave velocity test and dynamic penetration test are carefully compiled and corrected according to the data processing procedures recommended in the related research article [1]. All necessary information that helps develop the corresponding deterministic or probabilistic prediction models for gravelly soil liquefaction, including earthquake name and time, site name and its location, moment magnitude (Mw), peak ground acceleration, epicentral distance, bracketed duration, fines content, gravel content, average particle size, normalized dynamic penetration test blow count or normalized shear wave velocity, groundwater table, depth of gravelly soil deposit, total and effective overburden stress, the thickness of the impermeable capping layer, the thickness of the unsaturated zone between the groundwater table and capping layer, cyclic stress ratio for Mw = 7.5, and liquefaction information, are given for the datasets.

| S-EPMC8138722 | biostudies-literature

Recognition memory reconsolidation requires hippocampal Zif268.

Project description:Object recognition memory (ORM) serves to distinguish familiar items from novel ones. Reconsolidation is the process by which active memories are updated. The hippocampus is engaged in ORM reconsolidation through a mechanism involving induction of long-term potentiation (LTP). The transcription factor Zif268 is essential for hippocampal LTP maintenance and has been frequently associated with memory processes. However, its possible involvement in ORM reconsolidation has not been determined conclusively. Using Zif268 antisense oligonucleotides in combination with behavioural, biochemical and electrophysiological tools in rats, we found that hippocampal Zif268 is necessary to update ORM through reconsolidation but not to retrieve it or keep it stored. Our results also suggest that knocking down hippocampal Zif268 during ORM reconsolidation deletes the active recognition memory trace.

| S-EPMC6851087 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data