181 research outputs found
Novel Sustainable Structural Materials By Using Benign Waste Materials
We propose a Green Cement Paradigm (GCPa) for fabricating environmentally friendly cementitious materials. By using GCPa, we report for the first time, the usage of Class C Fly Ash as a sole source of cementitous phase without any activation by alkali. During this study, Class C Fly Ash, and its composites with sand were fabricated at different compaction stresses by maintaining a low w/c (w-water, c-cement) ratio of 0.17-0.24 in the compacts. The porosity and the number of days for curing played a significant role in the evolution of compressive strength. The experimental results indicate that the curing for 28 days is the optimum time required for strength development. For example, the Class C Fly Ash samples cold pressed at ~86 MPa and cured for 28 days showed a compressive strength of ~29.5 MPa. The effect of additional Ca(OH)2, high temperature curing and carbonation on the compressive strength development of the class C FA samples is reported. SEM, EDS, TGA/DSC and XRD investigations were employed to explain the obtained results. The possibility of fabricating lignin based polymer composites was investigated. The mechanical properties of the composites were reported in terms of yield strength and flexural strength
Kināyah as a figure of speech in the Qur’an: an analysis of four English translations
Since figurative expressions involve a double interpretation and are easily misinterpreted, they can pose a serious problem in translation. Kināyah, a central figure of speech in the Arabic rhetorical tradition, is extensively employed in the Qur’an. While several existing studies examine how Qur’anic figurative expressions are translated into English, this is to my knowledge the first substantial study to focus on kināyah.
The study first considers the main Arabic figures of speech (ʾistiᶜārah, tashbīh, majāz al-mursal, kināyah) plus the main English ones (metaphor, simile, metonymy, synecdoche), demonstrating that there is no equivalent figure to kināyah in English. Forty-five Qur’anic kināyah expressions are then chosen, pursuant to al-Jurjāni’s definition of kināyah and the majority of Qur’anic exegetes. Using authoritative Arabic and English dictionaries and exegeses, these expressions are analysed contextually in order to understand the meaning and purpose of each kināyah. This is followed by a target text (TT) analysis of four well-known English Qur’an translations: Ali, al-Hilali & Khan, Saheeh International, and Abdel Haleem. The study examines: (1) how the four translations render each kināyah, (2) the intelligibility of the renditions, (3) whether there is any loss of meaning, (4) whether the renditions maintain the function of the ST kināyah, and (5) consistency in rendering the same kināyah when it occurs in different ʾāyahs (Qur’anic verses).
Underlining the fact that kināyah has no equivalent in Western rhetoric, the study shows that while majāz mursal has similar features to the western metonymy and synecdoche, kināyah does not. Therefore, the use of the terms kināyah and majāz mursal for ‘metonymy’ and vice versa, as in most dictionaries and some studies, is incorrect. The study also shows that although the selected Qur’anic translations are largely source-oriented, the translators were able to render most of the kināyah expressions successfully. However, the translations were frequently not able to maintain the functions of the kināyah, apart from the euphemistic one, demonstrating that they prioritise meaning over function. In cases where there is a probable loss of the intended meaning, the translators employ footnotes, paraphrasing, or explicitation. The translations of Saheeh International and particularly Abdel Haleem are more intelligible than the rest due to their choice of contemporary and idiomatic vocabulary. Hence, they use footnotes and paraphrasing much less than Ali and Al-Hilali & Khan. For the most part the translations are consistent, especially Saheeh International and Abdel Haleem
An adaptive distributed Intrusion detection system architecture using multi agents
Intrusion detection systems are used for monitoring the network data, analyze them and find the intrusions if any. The major issues with these systems are the time taken for analysis, transfer of bulk data from one part of the network to another, high false positives and adaptability to the future threats. These issues are addressed here by devising a framework for intrusion detection. Here, various types of co-operating agents are distributed in the network for monitoring, analyzing, detecting and reporting. Analysis and detection agents are the mobile agents which are the primary detection modules for detecting intrusions. Their mobility eliminates the transfer of bulk data for processing. An algorithm named territory is proposed to avoid interference of one analysis agent with another one. A communication layout of the analysis and detection module with other modules is depicted. The inter-agent communication reduces the false positives significantly. It also facilitates the identification of distributed types of attacks. The co-ordinator agents log various events and summarize the activities in its network. It also communicates with co-ordinator agents of other networks. The system is highly scalable by increasing the number of various agents if needed. Centralized processing is avoided here to evade single point of failure. We created a prototype and the experiments done gave very promising results showing the effectiveness of the system
A critical review on the performance of pile-supported rail embankments under cyclic loading: Numerical modeling approach
Searching for economical and practical solutions to increase any transport substructures protection and stability is critical for ensuring the long-term viability and adequate load-bearing capacity. Piles are increasingly being used as an economical and environmentally sustainable solution to enhance the strength of soft subgrade soils on which embankments are raised. As per the available literature, there are two main strategies used to explain railway embankments performance: experimental approaches and numerical simulations on a broad scale. The purpose of this study is to examine the state-of-the-art literature on numerical modeling methods adopted to assess the performance of pile-supported rail embankments subjected to cyclic loading. The paper addresses the main results from various numerical methods to explain the appropriate mechanisms associated with the load deformation response. It also presents the key issues and drawbacks of these numerical methods concerning rail embankment development while outlining the specific shortcomings and research gaps relevant to enhanced future design and analysis. (c) 2021 by the authors. Licensee MDPI, Basel, Switzerland
Rice husk templated water treatment sludge as low cost dye and metal adsorbent
AbstractThe preparation of adsorbents at low cost as alternatives to the expensive ones in the treatment processes of water and wastewater is the interest of the researchers worldwide. Here, a novel cheap mesoporous adsorbent was prepared via the recycling of wastes namely water treatment sludge and rice husk (RH) as textural modifier. Surface area and pore dimensions were optimized against RH ratio. The mesoporous sludge was employed in adsorption of rosaniline dye, Pb2+, Ni2+ and chlorine from aqueous solutions under dynamic experimental conditions. It was found that the initial dye concentration and textural structure of the adsorbent played important roles in adsorption capacity. The reusability test shows the ease desorption of dye with slightly alkaline water (pH=8) indicating the stability and reusability of the ceramic adsorbent for several times. For metallic cations, the characteristics (ionic radius and ΔHhyd) of ions affect the adsorption affinity. Chlorine adsorption is controlled by the cation exchange capacity(CEC)
Bereavement reduces neutrophil oxidative burst only in older adults: role of the HPA axis and immunesenescence
Background The effect of the chronic stress of bereavement on immunity is poorly understood. Previous studies have demonstrated negative effects on immunity in older adults, and those who report higher depressive symptoms. The aim of the present study was to compare the effect of bereavement on neutrophil function in healthy young and old adults, also assessing serum levels of the stress hormones, cortisol and dehydroepiandrosterone sulphate (DHEAS). 41 young (mean age 32 years) and 52 older adults (mean age 72 years), bereaved and non-bereaved, took part in the study. They completed questionnaires on socio-demographic and health behaviour characteristics, as well as psychosocial variables, and provided a blood sample for analysis of neutrophil function (phagocytosis and reactive oxygen species (ROS) production) and stress hormone analysis. Results Bereaved participants in both age groups reported more symptoms of depression and anxiety than controls and scored moderately highly on bereavement-specific questionnaires for these symptoms. Despite this, young bereaved participants showed robust neutrophil function when compared to age-matched non-bereaved controls, and comparable stress hormone levels, while reduced neutrophil ROS production and raised stress hormone levels (cortisol:DHEAS ratio) were seen in the older bereaved group compared to their age-matched controls. Conclusions Reduced neutrophil function among older bereaved participants may be the result of the inability to maintain stress hormone balance, specifically the cortisol:DHEAS ratio
Collective impact : operationalizing a framework to coordinate community services
The Maternal, Infant, and Early Childhood Home Visiting (MIECHV) program provides comprehensive early childhood services. Federal agencies emphasize coordination of stakeholders for systems-building. Designing a well-coordinated system is complex. We reviewed MIECHV’s literature and program documents to identify community-coordination infrastructure elements. We designed visual frameworks for each model to display infrastructure, components, and connections. In the independent point of entry model, families access services directly. In the coordinated point of entry model, a centralized intake and referral structure supports system coordination. In the collective impact model, relevant community stakeholders actively and collaboratively participate in service coordination. Visual frameworks allow stakeholders to align on process and infrastructure of their programs to facilitate planning activities, use these frameworks to identify whether the model under which they operate is ideal, and then evolve their infrastructure.Includes bibliographical references (page 8-9)
Using Process Mining to Assess the Fidelity of a Home Visiting Program
Background: The Maternal, Infant, and Early Childhood Home Visiting (MIECHV) program is a federal public health initiative which supports at-risk families through evidence-based programs and promising approaches for pregnant women, and childhood development for children aged 0 to 5. These public health program funding mechanisms commonly include process evaluation mandates.
Purpose: The use of process mining was explored as a methodology to assess the fidelity of the MIECHV programs’ actual workflow to that of their intended models.
Methods: Research Electronic Data Capture (REDCap) data files that were populated with program process data elements from the local implementing agencies were mined. The focus was on three main variables: participant identification, activity labels, and timestamps. These variables were imported into the Disco process-mining software. Disco was used to develop process maps to track process pathways and compare the actual workflow against the intended model.
Results: Using process mining as a diagnostic tool, fidelity to the MIECHV process model was assessed, identifying a total of 262 different process variations. The 15 most frequent variations represent 60.7% of the total pool of process variations, 13 of which were deemed to have fidelity to the intended model. Analysis of the variations indicated that many activities in the intended process were skipped or implemented out of sequence.
Implications: Process mining is a useful tool for organizations to visually display, track, understand, compare, and improve their workflow processes. This method should be considered by programs as complex as MIECHV to improve the data reporting and the identification of opportunities to strengthen programs
Visualizing Complex Adaptive Systems: A Case Study of the Missouri Maternal, Infant, and Early Childhood Home Visiting Program
Background: The Maternal, Infant, and Early Childhood Home Visiting (MIECHV) program was created by the 2010 Patient Protection and Affordable Care Act. MIECHV provides comprehensive services to at-risk families through evidence-based home visiting programs.
Purpose: The following question is addressed: Does the Missouri MIECHV system meet the definition of a complex adaptive system (CAS)?
Methods: A systematic review was conducted of documents related to MIECHV programs (federal, state, and local levels), and to affiliated programs with a home visiting and early childhood (aged birth to 5 years) scope. The organizations’ fit was identified for the scope of early childhood home visiting programs, and then its relationship extracted to MIECHV and its affiliates.
Results: MIECHV meets the definition of a CAS, being dynamic, massively entangled, scale independent, transformative, and emergent. Over 250 organizations were identified; 19 federal and 79 state organizations; 24 nonprofits at the federal level, 31 at the state; over 150 community-level agencies; and 13 home visiting models implemented in Missouri.
Implications: A considerable amount of organizational complexity exists within the MIECHV system and among its affiliates with a home visiting and early childhood scope. The complexity of the system challenges its potential for effective and efficient implementation, coordination, sustainability, and evaluation, and increases the potential for redundancy, overlap, and fragmentation. Evaluating a CAS requires acknowledgement of its complexity, beyond traditional approaches to evaluation. Creating visualization tools of federal, state, and local stakeholders and their relationships is a practical approach for aligning, organizing, and communicating the work flow
Simulation of tethered oligomers in nanochannels using multi-particle collision dynamics
The effect of a high Reynold's number, pressure-driven flow of a compressible
gas on the conformation of an oligomer tethered to the wall of a square-channel
is studied under both ideal solvent and poor solvent conditions using a hybrid
multiparticle collision dynamics and molecular dynamics algorithm. Unlike
previous studies, the flow field contains an elongational component in addition
to a shear component as well as fluid slip near the walls and results in a
Schmidt number for the polymer beads that is less than unity. In both solvent
regimes the oligomer is found to extend in the direction of flow. Under the
ideal solvent conditions, torsional twisting of the chain and aperiodic
cyclical dynamics are observed for the end of the oligomer. Under poor solvent
conditions, a metastable helix forms in the end of the chain despite the lack
of any attractive potential between beads in the oligomeric chain. The
formation of the helix is postulated to be the result of a solvent induced
chain collapse that has been confined to a single dimension by a strong flow
field.Comment: 15 pages, 13 figures, to appear in J. Chem. Phys., 201
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