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During the construction of coastal projects, the formation of seepage channels within the soil body, induced by fluctuating water pressure, can result in consequential damage to the soil structure, ultimately culminating in sudden water gushing sand disasters. In order to investigate the impact of static and dynamic seepage pressures on sand flow and water flow conditions, an intelligent water pressure loading device was devised to consistently apply a confining pressure of 60 kPa to the specimens. The three static seepage pressures and nine fluctuating seepage pressures were applied to the specimens under the condition of constant confining pressure to study the effect of static and dynamic seepage pressures on sand flow and flow conditions. The outcomes of the experiments revealed that, when the base water pressure of the dynamic seepage pressure is the same as the static seepage pressure, the cumulative seepage volume and permeation velocity of the dynamic seepage pressure are always larger than that of the static seepage pressure. Moreover, higher static pressures increase forces on particles, enhancing permeation velocity, and cumulative seepage volume. Notably, longer periods of pressure fluctuations in dynamic seepage pressures and lower basic water pressures weaken the effect of dynamic seepage pressures. [ABSTRACT FROM AUTHOR]

Nella Larsen's Quicksand (1928) demonstrates a situated form of Black cosmofeminism to capture the difficult process through which a deviant mixed-race heroine negotiates her place in the Black community. At core, Black cosmofeminism interrogates oppressive racial and sexual politics enacted in domestic, local, and national spheres to envision a more inclusive cosmopolitan US Black community open to sexually, racially, and nationally "impure" subjects. However, far from advocating the erasure of local identities, such a reimagining of the domestic Black community as cosmofeminist instead foregrounds group identification and communal bonding developed in response to transnational displacement and discrimination. Working in tandem with consumer cosmopolitanism, Black cosmofeminism places the African American woman consumer center stage and traces how her desire, body, and identity are not only constructed alongside globally circulated commodities but also made localized and resistant to the global commodification and sexualization of Black and mixed-raced women. [ABSTRACT FROM AUTHOR]

In the article, the feature of settlement, subsidence, and other deformations in the ground foundations of various structures built in complex engineering-geological conditions with the joint participation of some soils with a stable structure (subsidence loess, silt, low-strength technogenic, soluble) are performed on the example of the Gazakh cement plant, the development of a conceptual solution for the methods of installation in foundations on such soils has been reflected. Analyzing the results of the complex engineer-geological research conducted at the research facility, priority was given to the principle of improving the working conditions of the soils that form the basis of the facilities in order to prevent the predicted large-scale deformation, the application of a foundation system consisting of piles with a large length, with the bottom placed in a layer of argillite-like very stiff clay, was accepted as the most correct technical solution, the dimensions of the pile are determined and installed in the study area and it was determined that the chosen solution was justified by monitoring the deformations. [ABSTRACT FROM AUTHOR]

Swallowing of large objects and humans by quicksand fascinated writers for long time. Previously, it was believed that sand must contain liquid to achieve such characteristics. However, recently it has been proposed that even undampened loose sand (like in deserts) can swallow large objects and investigated in this paper. In this study, numerical simulations are performed using computational fluid dynamics (CFD) and discrete element method (DEM). The transition from packed to quicksand like state in granular material is obtained by passing gas near to minimum fluidization velocity and keeping bed stationary. It is observed in simulations that dry quicksand acts more like a fluid and the granular drag force due to penetration of intruder becomes isotropic and depth independent which is a deviation from packed bed. At the end of paper, the physics behind this behavior is explained by comparing force chains formed in packed and dry quicksand. Resistance force on intruder (a) Packed bed (b) Quicksand (c) Force chains in packed bed (d) Force chains in quicksand. Image 1 • Granular drag force acting on intruder during immersion in quicksand is investigated and compared with packed bed. • Quicksand acts like fluid and the granular drag force becomes isotropic and independent with immersion depth. • Reason for this deviation is due to absence of force chains in quicksand which are strong for dry packed bed of particles. [ABSTRACT FROM AUTHOR]

In his 2006 award winning monograph In Search of Nella Larsen: A Biography of the Color Line, George Hutchinson shed new light not only on the biographical facts of Nella Larsen’s life as a biracial individual coming of age during an “era when ‘race’ trumped” all relationships, even those of family, but also on the effects these experiences had on her psychologically, especially on her ability to forge a relational life. Given her socially and psychically untenable subject position as the “too dark to pass” child in a white family and the sense of isolation and, ultimately, abandonment, that attended it, it’s little wonder that Larsen’s autobiographically-informed fictional narratives can be read as sites of relational failure. In this article, I locate the narrative absences at the center of Larsen’s first novel, Quicksand, and examine the manner in which they source the relational failures that render the protagonist, Helga Crane, incapable of fulfilling her promise as, in Deborah McDowell’s words, a “daring and unconventional heroine” (xi). Not only does the palimpsestic presence of the black paternal impede Helga’s quest for social legitimacy and place, the present absence of the white maternal, arguably a more critical lacuna, serves as the experiential and psychological source of Helga’s fundamental “lack somewhere”: her failure to develop a relational subjectivity.

Under the fragile geological environment conditions in Shanghai, intensively distributed underground pipelines and large-scale development of underground space have brought severe challenges to urban geological safety. This paper starts with the “shallow sand layer” distribution area, where surface collapse disasters occur frequently, systematically investigates the typical characteristics and influencing factors of the disaster, then researches the risk assessment of continual collapse disasters and monitoring of the early warning of hidden dangers. Firstly, the indicator system for risk assessment needs to be constructed. The relative index data are classified as two aspects of fatalness and vulnerability, including geological and hydrogeological engineering, underground pipelines and underground space, meteorological hydrology, basic geographic information, human engineering activities, and human risk resistance capabilities. This was carried out to form hierarchical zoning of the risk for land collapse disasters in Shanghai by using the ArcGIS program as a platform. Secondly, the prevention and control of urban land subsidence disasters is a multi-source and multi-dimensional endeavor. It is necessary to conduct in-depth investigations on the affecting factors and establish a basic data system, including geological conditions and underground facilities, etc. Further improving and refining risk zoning is a prerequisite for the effective prevention and control of urban ground collapse disasters; comprehensive application with geological radar, three-dimensional laser scanning, automatic monitoring, and other investigation methods are performed on this bases. Through multi-stage work such as census, detailed investigation, and monitoring, it is possible to investigate and monitor the abnormal hidden dangers of different objects, for instance, underground facilities, underground cavities, soil displacement, groundwater level, etc. Furthermore, it helps achieve the early warning of ground collapse disasters effectively. Relevant research results have great significance on urban refined management and safe operations, which will promote the prevention and control of ground subsidence disasters in Shanghai, gradually changing to a holistic, long-term, and systematic direction. [ABSTRACT FROM AUTHOR]

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The article presents an essay that explores the nature of the concept of quicksand across a range of texts including the books "Living On: Borderlines" by philosopher Jacques Derrida and "The Beast and the Sovereign." Topics discussed include the book "Giving Birth" by Margaret Atwood that precedes Derrida's text.

Abstract The 3-D spatial and mechanical features of nano-topography can create alternative environments, which influence cellular response. In this paper, murine fibroblast cells were grown on surfaces characterized by protruding nanotubes. Cells cultured on such nano-structured surface exhibit stronger cellular adhesion compared to control groups, but despite the fact that stronger adhesion is generally believed to promote cell cycle progression, the time cells spend in G1 phase is doubled. This apparent contradiction is solved by confocal microscopy analysis, which shows that the nano-topography inhibits actin stress fiber formation. In turn, this impairs RhoA activation, which is required to suppress the inhibition of cell cycle progression imposed by p21/p27. This finding suggests that the generation of stress fibers, required to impose the homeostatic intracellular tension, rather than cell adhesion/spreading is the limiting factor for cell cycle progression. Indeed, nano-topography could represent a unique tool to inhibit proliferation in adherent well-spread cells. Graphical abstract Nano-topography influences cell mechanotransduction, by inhibiting stress fiber, formation. The lack of stress fibers blocks the transmission of out-to-inside force from, adhesion points to actin cytoskeleton and, consequently, the achievement of the critical, tensional homeostasis, which is required for RhoA activation and RhoA-dependent, suppression of p21 levels and cell cycle progression. Unlabelled Image [ABSTRACT FROM AUTHOR]

A quicksand disaster through a borehole occurred in Longde coal mine. A lot of aeolian sand, the volume of which is between 310,000 m3 and 380,000 m3, has submerged into the underground space in about 70.5 h. The volume flux of quicksand cannot be calculated accurately by the empirical method. Based on the method of fluid mechanics, an all-purpose computing method for quicksand disaster through a borehole was proposed. The result shows that the inrush volume of sand into underground space was between 310,000 m3 and 350,000 m3, which was consistent with the actual result. To apply and popularize this method, the impact laws of water yield properties of an aquifer on the volume flux were discussed. The all-purpose computing method can be suitably used for the volume flux calculation of quicksand disaster through the borehole. [ABSTRACT FROM AUTHOR]

Groundwater inrush and quicksand from the underlying aquifers are two typical geological hazards during underground constructions in Shanghai region, China. The objective of this work is to give a zoning study on confined aquifers and quicksand geology in Shanghai region and provide helpful decision-making information for the government, urban planners and designers. The hydrogeological characteristics of the confined aquifers in Shanghai are collected, and two different criteria are then proposed for mapping the aquifers. The characteristics and distribution of the soil stratum, in which quicksand would occur, are then presented, and an index system for quicksand hazard and vulnerability assessment is proposed. Furthermore, the quicksand risk in different zones of Shanghai is evaluated using a semiquantitative approach, and the management zoning is developed by considering the urban planning of Shanghai. The zoning maps of confined aquifers and quicksand risk are obtained, and the high-risk zone can be directly identified from the zoning maps. This is greatly helpful for the future urban planning and underground constructions in Shanghai region. The proposed method for quicksand hazard and vulnerability assessment is also applicable for other cities undergoing geological hazards caused by confined water inrush and quicksand. [ABSTRACT FROM AUTHOR]

This paper deals with the numerical simulation of the quicksand phenomenon using a coupled Discrete Elements - Lattice Boltzmann hydromechanical model. After the presentation of the developed numerical model, simulations of ascending fluid flow through granular deposits are performed. The simulations show that the quicksand actually triggers for a hydraulic gradient very close to the critical hydraulic gradient calculated from the global analysis of classical soil mechanics, that is, when the resultant of the applied external pressure balances submerged weight of the deposit. Moreover, they point out that the quicksand phenomenon does not occur only for hydraulic gradients above the critical hydraulic gradient, but also in some cases with slightly lower gradients. In such cases, a more permeable zone is first gradually built at the bottom of the deposit through a grain rearrangement, which increases the hydraulic gradient in the upper zones and triggers the phenomenon. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper presents a numerical simulation of quicksand or sand flow hazard through the broken rock mass in the caving zone due to coal mining based on DEM.The panel 22402 of the Halagou Coalmine was taken as the study site in this paper. The fragment-size distribution of caving zone was analyzed by using the fractal theory and then a numerical model of quicksand through the broken rock mass of caving zone with random shape was constructed by using DEM according to the fragment-size distribution. The simulation results show that the caving zone with large voids or pores and good connectivity are the dominant pathways for sand migration；the voids and pores in the caving zone can store the aeolian sand. The poorly graded rock mass in caving zone has a certain effect to block the sand flow；the velocity profiles of sand flow are of spindle type which mean that the sand flow velocities along the centerline are larger than those near the wall. [ABSTRACT FROM AUTHOR]

Despite studies examining quicksand over the years, there remains a void of investigations into the meaning and value of quicksand in the lives of recreational enthusiasts, most notably the community of people dubbed "sinkers." Sinkers are quicksand enthusiasts that crave the sensation of being stuck in deep mud while being sucked downward. Researchers in this study used an interpretive design where naturalistic research methods allowed for meaningful information to be observed and described by studying the lives, stories, behaviors, and relationships of quicksand enthusiasts. In an effort to further this understanding, the researchers examined both conditional and behavioral social norms of an activity that is often viewed by the mainstream as unique and perhaps bizarre. Results from this study may help educate and inform park and other public resource managers about the social world of sinkers and what motivates sinkers to pursue quicksand as a recreational activity. This study has given us a qualitative tour into the social world of a unique group of outdoor enthusiasts that love quicksand. [ABSTRACT FROM AUTHOR]

Environmental change increasingly effects internal and external patterns of human movement around the globe. Whether due to loss of livelihood from rising sea waters, degradation of arable land, or increased frequency and severity of storms, people are on the move. This article looks at environmental factors driving this new wave of migrants and provides a set of 'guiding principles' for policymakers, international institutions, NGOs, academia, and the think tank community to create new policies, and the obstacles they may face in implementation. [ABSTRACT FROM AUTHOR]

Copyright of Foreign Literature Studies is the property of Foreign Literature Studies and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

First order reliability method (FORM) is generally used for reliability analysis in geotechnical engineering. This article adopts generalized regression neural network (GRNN) based FORM, Gaussian process regression (GPR) based FORM and multivariate adaptive regression spline (MARS) based FORM for reliability analysis of quick sand condition. GRNN is related to the radial basis function (RBF) network. GPR is developed based on probabilistic framework. MARS is a nonparametric regression technique. A comparative study has been carried out between the developed models. The performance of GPR based FORM and MARS based FORM match well with the FORM. This article gives the alternative methods for reliability analysis of quick sand condition. [ABSTRACT FROM AUTHOR]

The widespread use of social media and its potential to hinder academic performance has received the attention of researchers and is a growing concern of educators. This phenomenological study explored the perceived impact of social media on the educational experiences of university students in the United States, both in and out of the classroom. Analysis of semi-structured interviews revealed several pervasive themes, all of which can be viewed as barriers to academic success. Participants reported that using social media during academic activities diminishes achievement, increases the amount of time it takes to complete tasks, and reduces how much information students retain from study and lecture sessions. Additionally, participants indicated how a lack of situational and topic interest increases social media's temptation. We argue that educators and students would benefit from a more complete understanding of social media's role as a barrier to academic success. Implications for educators are discussed. [ABSTRACT FROM AUTHOR]

In coal mining, a poorly sealed borehole is one of the channels that can lead to an inrush of water and quicksand movement, seriously compromising the safety of the coal mine. In this paper, we used the water inrush and quicksand incident at Longde Coal Mine as an example in order to investigate the mechanism of water inrush and quicksand movement induced by a borehole, as well as to develop measures for the prevention and remediation of such problems. Two sand funnel models and a water inrush outlet model are introduced from which to calculate the flow of the water and quicksand; a comparison of the two shows that the flow predicted by the water inrush outlet model is more consistent with observations from the accident than the sand funnel models. Based on the water inrush outlet model, the aquifer thickness and borehole diameter are the two key factors affecting the flow. The aquifer channel is inferred as tubular, with its diameter gradually decreasing from ground surface to underground, and a time-dependent surface subsidence model is constructed. Finally, we develop a prevention method, 'Prior to mining development, borehole should be investigated and plugged for prevention,' and propose a remediation method, 'Changing the pipeline flow into fracture flow, followed by changing the fracture flow into pore flow, and finally grouting and plugging.' [ABSTRACT FROM AUTHOR]