scholarly journals Using plants to remediate or manage metal-polluted soils: an overview on the current state of phytotechnologies

2021 ◽  
Vol 43 ◽  
pp. e58283
Author(s):  
Clístenes Williams Araújo do Nascimento ◽  
Caroline Miranda Biondi ◽  
Fernando Bruno Vieira da Silva ◽  
Luiz Henrique Vieira Lima
Keyword(s):  
Large Scale ◽  
State Of The Art ◽  
Cost Effective ◽  
Time Frame ◽  
Contaminated Site ◽  
Polluted Soils ◽  
Mining Sites ◽  
Current State ◽  
Remedial Actions ◽  
The Tropics

Soil contamination by metals threatens both the environment and human health and hence requires remedial actions. The conventional approach of removing polluted soils and replacing them with clean soils (excavation) is very costly for low-value sites and not feasible on a large scale. In this scenario, phytoremediation emerged as a promising cost-effective and environmentally-friendly technology to render metals less bioavailable (phytostabilization) or clean up metal-polluted soils (phytoextraction). Phytostabilization has demonstrable successes in mining sites and brownfields. On the other hand, phytoextraction still has few examples of successful applications. Either by using hyperaccumulating plants or high biomass plants induced to accumulate metals through chelator addition to the soil, major phytoextraction bottlenecks remain, mainly the extended time frame to remediation and lack of revenue from the land during the process. Due to these drawbacks, phytomanagement has been proposed to provide economic, environmental, and social benefits until the contaminated site returns to productive usage. Here, we review the evolution, promises, and limitations of these phytotechnologies. Despite the lack of commercial phytoextraction operations, there have been significant advances in understanding phytotechnologies' main constraints. Further investigation on new plant species, especially in the tropics, and soil amendments can potentially provide the basis to transform phytoextraction into an operational metal clean-up technology in the future. However, at the current state of the art, phytotechnology is moving the focus from remediation technologies to pollution attenuation and palliative cares.

scholarly journals A Step by Step Methodology for Building Sustainable Cementitious Matrices

2020 ◽  
Vol 10 (8) ◽  
pp. 2955 ◽  
Author(s):  
Styliani Papatzani ◽  
Kevin Paine
Keyword(s):  
Fly Ash ◽  
Portland Cement ◽  
Silica Fume ◽  
Carbon Footprint ◽  
State Of The Art ◽  
Cost Effective ◽  
Strength Development ◽  
Low Carbon ◽  
Current State ◽  
First Time

In an effort to produce cost-effective and environmentally friendly cementitious binders. mainly ternary (Portland cement + limestone + pozzolanas) formulations have been investigated so far. Various proportions of constituents have been suggested, all, however, employing typical Portland cement (PC) substitution rates, as prescribed by the current codes. With the current paper a step by step methodology on developing low carbon footprint binary, ternary and quaternary cementitious binders is presented (PC replacement up to 57%). Best performing binary (60% PC and 40% LS (limestone)) and ternary formulations (60% PC, 20% LS, 20% FA (fly ash) or 43% PC, 20% LS 37% FA) were selected on the grounds of sustainability and strength development and were further optimized with the addition of silica fume. For the first time a protocol for successfully selecting and testing binders was discussed and the combined effect of highly pozzolanic constituents in low PC content formulations was assessed and a number of successful matrices were recommended. The present paper enriched the current state of the art in composite low carbon footprint cementitious binders and can serve as a basis for further enhancements by other researchers in the field.

scholarly journals Dengue Situation in Bangladesh: An Epidemiological Shift in terms of Morbidity and Mortality

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Pulak Mutsuddy ◽  
Sanya Tahmina Jhora ◽  
Abul Khair Mohammad Shamsuzzaman ◽  
S. M. Golam Kaisar ◽  
Md Nasir Ahmed Khan
Keyword(s):  
Large Scale ◽  
Monsoon Season ◽  
Public Health Problem ◽  
Cost Effective ◽  
Time Frame ◽  
Morbidity And Mortality ◽  
Effective Vaccine ◽  
Vector Borne Diseases ◽  
Research Organizations ◽  
Post Monsoon Season

The escalating dengue situation in Bangladesh has been emerging as a serious public health problem in terms of morbidity and mortality. Results of analysis of 40,476 cases of Bangladesh occurring during 2000–2017 indicated that 49.73% of the dengue cases occurred during the monsoon season (May–August) and 49.22% during the post-monsoon season (September–December). However, data also showed that, since 2014, these trends have been changing, and dengue cases have been reported during the pre-monsoon season. During 2015–2017, in the pre-monsoon season, the dengue cases were reported to be more than seven times higher compared to the previous 14 years. The findings closely correlate with those of the pre-monsoon Aedes vector survey which revealed the presence of high density of larva and pupa of the dengue vectors in the environment all the year round. In our study, climate changes, such as average rainfall, humidity, and temperature, after 2014, and rapid unplanned urbanization were the strong predictors of an imbalance in the existing ecology that has led to increase in dengue cases in 2016 and the emergence of the chikungunya virus for the first time in Bangladesh in 2017. Although 2018 dengue data are relevant but not included in this study due to study time frame, it is interesting to report an increase in the number of dengue cases in pre (2016) and post (2018, which is highest within 18 years) chikungunya outbreak, which favors the study hypothesis. Despite the efforts to control dengue, based primarily on the vector control and case management, the burden and costs of the disease and similar vector-borne diseases will continue to grow in future in our country. Developing a cost-effective vaccine against all the 4 strains of dengue remains a challenge. The CDC, in collaboration with other research organizations, may come forward to initiate and coordinate a large-scale randomized clinical trial of an effective dengue vaccine in Bangladesh.

scholarly journals DNA Methods: Critical Review of Innovative Approaches

2002 ◽  
Vol 85 (3) ◽  
pp. 797-800
Author(s):  
Esther J Kok ◽  
Henk J M Aarts ◽  
A M Angeline van Hoef ◽  
Harry A Kuiper
Keyword(s):  
Genetically Modified Organisms ◽  
State Of The Art ◽  
Cost Effective ◽  
Detection Methods ◽  
Market Place ◽  
Gmo Detection ◽  
Current State ◽  
Detection And Identification ◽  
European Regulations ◽  
Labeling Requirements

Abstract The presence of ingredients derived from genetically modified organisms (GMOs) in food products in the market place is subject to a number of European regulations that stipulate which product consisting of or containing GMO-derived ingredients should be labeled as such. In order to maintain these labeling requirements, a variety of different GMO detection methods have been developed to screen for either the presence of DNA or protein derived from (approved) GM varieties. Recent incidents where unapproved GM varieties entered the European market show that more powerful GMO detection and identification methods will be needed to maintain European labeling requirements in an adequate, efficient, and cost-effective way. This report discusses the current state-of-the-art as well as future developments in GMO detection.

AN APPLICATION CONCEPT OF THE FIBRE-OPTICAL TECHNOLOGY IN GEODETIC MONITORING OF ENGINEERING OBJECTS

2017 ◽  
Vol 166 (46) ◽  
pp. 60-74
Author(s):  
Krzysztof Karsznia ◽  
Konrad Podawca
Keyword(s):  
Risk Management ◽  
Large Scale ◽  
State Of The Art ◽  
Monitoring Systems ◽  
Management Approach ◽  
Engineering Structures ◽  
Geoinformation Systems ◽  
Current State ◽  
Modern Engineering ◽  
Integrated Risk

Monitoring of structures and other different field objects undoubtedly belongs to the main issues of modern engineering. The use of technologies making it possible to implement structural monitoring makes it possible to build an integrated risk management approach combining instrumental solutions with geoinformation systems. In the studies of engineering structures, there is physical monitoring mainly used for examining the physical state of the object - so-called SHM ("Structural Health Monitoring"). However, very important role is also played by geodetic monitoring systems (GMS). The progress observed in the field of IT and automatics has opened new possibilities of using integrated systems on other, often large-scale objects. Based on the current state-of-the-art, the article presents the concept of integration approaches of physical and geodetic monitoring systems in order to develop useful guidelines for further construction of an expert risk management system.

Real Time Simulation for High Fidelity Multibody Dynamics and Mechatronic Systems

2014 ◽  
Author(s):  
William Prescott
Keyword(s):  
Real Time ◽  
Multibody Dynamics ◽  
Large Scale ◽  
State Of The Art ◽  
High Fidelity ◽  
Implicit Integration ◽  
Mechatronic Systems ◽  
Vehicle Simulation ◽  
Current State ◽  
Time Simulation

This paper will investigate the use of large scale multibody dynamics (MBD) models for real-time vehicle simulation. Current state of the art in the real-time solution of vehicle uses 15 degree of freedom models, but there is a need for higher-fidelity systems. To increase the fidelity of models uses this paper will propose the use of the following techniques: implicit integration, parallel processing and co-simulation in a real-time environment.

scholarly journals Crop Rotation Modeling for Deep Learning-Based Parcel Classification from Satellite Time Series

2021 ◽  
Vol 13 (22) ◽  
pp. 4599
Author(s):  
Félix Quinton ◽  
Loic Landrieu
Keyword(s):  
Time Series ◽  
Deep Learning ◽  
Crop Rotation ◽  
Large Scale ◽  
State Of The Art ◽  
Crop Rotations ◽  
Learning Approach ◽  
Type Mapping ◽  
Current State ◽  
Crop Type

While annual crop rotations play a crucial role for agricultural optimization, they have been largely ignored for automated crop type mapping. In this paper, we take advantage of the increasing quantity of annotated satellite data to propose to model simultaneously the inter- and intra-annual agricultural dynamics of yearly parcel classification with a deep learning approach. Along with simple training adjustments, our model provides an improvement of over 6.3% mIoU over the current state-of-the-art of crop classification, and a reduction of over 21% of the error rate. Furthermore, we release the first large-scale multi-year agricultural dataset with over 300,000 annotated parcels.

Esthetic Rehabilitation With Nanohybrid Composite: Case Report Series

2020 ◽  
Vol 11 (2) ◽  
pp. 251-256
Author(s):  
Shazeena Qaiser ◽  
Darshana Devadiga ◽  
Mithra N Hegde
Keyword(s):  
State Of The Art ◽  
Case Reports ◽  
Cost Effective ◽  
Composite Resins ◽  
Class Iii ◽  
Current State ◽  
First Case ◽  
High Smoothness ◽  
Nanohybrid Composite ◽  
Recent Addition

Composite resins represent the current state of the art in the field of restorative materials, for they present a standard aesthetic potential with satisfactory durability and are less cost-effective than a comparable ceramic restoration. The most recent addition to this is a nanohybrid direct composite that demonstrates exceptional handling properties and superior aesthetics. These series of case reports illustrate the three different scenarios where nanohybrid composite was used as a direct restorative material owing to its high smoothness and favorable mechanical properties; the first case being the fracture of an upper lateral incisor, second of Class IV caries in upper central incisors, and lastly the discolored restoration and Class III caries in upper central incisors. The nanohybrids used provided an acceptable color match in all the three cases with a conservative technique and were relatively easy to maintain.

On Establishing the Limits of a Virtual Test Rig

2001 ◽  
Author(s):  
D. Lee Hill ◽  
Zheji Liu ◽  
Jim Sorokes
Keyword(s):  
State Of The Art ◽  
Cost Effective ◽  
Low Flow ◽  
Test Rig ◽  
Flow Paths ◽  
Stage Design ◽  
Virtual Test ◽  
Current State ◽  
Computational Fluid Dynamics Cfd ◽  
Flow Stage

Abstract The use of a virtual test rig to numerically test turbomachinery hardware can be extremely cost effective if the results obtained are physically correct and relatively accurate. The literature clearly shows that a lot of emphasis has been placed on single component validation optimized for a single operation point. There are few studies, however, that have clearly documented the numerical issues surrounding the modeling of a complete stage of a centrifugal compressor across its operating range. This effort uses a generic low flow stage design to demonstrate the accuracy to expect from the current state-of-the-art technology found in both commercial and research computational fluid dynamics (CFD) software. Even effects stemming from secondary flow paths are considered in this study. For design and off-design operation toward surge, 360-degree transient calculations are compared to those obtained from using the steady state fixed-rotor approximation. Finally, all work is ultimately compared to detailed test data obtained from single stage testing.

scholarly journals Fast consensus in a large-scale multi-agent system with directed graphs using time-delayed measurements

2019 ◽  
Vol 377 (2153) ◽  
pp. 20180130 ◽  
Author(s):  
Adrián Ramírez ◽  
Rifat Sipahi ◽  
Sabine Mondié ◽  
Rubén Garrido
Keyword(s):  
Large Scale ◽  
State Of The Art ◽  
Directed Graphs ◽  
Graph Laplacian ◽  
Delay Systems ◽  
Multi Agent Systems ◽  
Current State ◽  
Complex Eigenvalues ◽  
Multi Agent ◽  
Delayed Measurements

This article is on fast-consensus reaching in a class of multi-agent systems (MAS). We present an analytical approach to tune controllers for the agents based on the premise that delayed measurements in the controller can be preferable to standard controllers relying only on current measurements. Controller tuning in this setting is however challenging due to the presence of delays. To tackle this problem, we propose an analytic geometry approach. The key contribution is that the tuning can be implemented for complex eigenvalues of the arising graph Laplacian of the network, complementing the current state of the art, which is limited to real eigenvalues. Results, therefore, extend our knowledge beyond symmetric graphs and enable the study of the MAS under directed graphs. This article is part of the theme issue ‘Nonlinear dynamics of delay systems’.

scholarly journals Scalable batch-correction method for integrating large-scale single-cell transcriptomes

2021 ◽  
Author(s):  
Xiangchun Li ◽  
Xilin Shen
Keyword(s):  
Single Cell ◽  
Expression Profile ◽  
Large Scale ◽  
State Of The Art ◽  
Correction Method ◽  
Feature Representation ◽  
Batch Correction ◽  
Data Alignment ◽  
Current State ◽  
Core Idea

Integration of the evolving large-scale single-cell transcriptomes requires scalable batch-correction approaches. Here we propose a simple batch-correction method that is scalable for integrating super large-scale single-cell transcriptomes from diverse sources. The core idea of the method is encoding batch information of each cell as a trainable parameter and added to its expression profile; subsequently, a contrastive learning approach is used to learn feature representation of the additive expression profile. We demonstrate the scalability of the proposed method by integrating 18 million cells obtained from the Human Cell Atlas. Our benchmark comparisons with current state-of-the-art single-cell integration methods demonstrated that our method could achieve comparable data alignment and cluster preservation. Our study would facilitate the integration of super large-scale single-cell transcriptomes. The source code is available at https://github.com/xilinshen/Fugue.

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