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This pioneering study utilizes Flame Atomic Absorption Spectroscopy (FAAS) and Picosecond Laser-Induced Breakdown Spectroscopy (Ps-LIBS) to quantify heavy metal contents in samples of Lactuca sativa L. and Trifolium alexandrinum L. collected from Banha and Giza, Egypt for the first time. In order to enhance the performance of Ps-LIBS, laser parameters were carefully optimized. Expressly, laser energy was set to 100 ± 5% J/cm², pulse duration was calibrated to 170 picoseconds, and 1064 nm Nd: YAG pulses were employed. This optimization facilitated the creation of linear LIBS calibration curves, a crucial element in ensuring precise elemental quantification and bolstering the overall analytical reliability. The assessment of pollution indices revealed concerningly high levels of copper, nickel, and cadmium consistently across all study sites. Lactuca sativa L. and Trifolium alexandrinum L. also demonstrated multiple metals' bioaccumulation factors (>1), further underscoring the potential health risks associated with copper, nickel, and cadmium contents. Given these findings, it is imperative to recommend constructing a dedicated wastewater treatment facility to address Al Mansouria village's environmental challenges in the Giza governorate. [ABSTRACT FROM AUTHOR]

The impacts of COVID-19 pandemic on construction project management are not documented and not well understood, which leaves project stakeholders with no guiding information to respond to such threats and no lessons learned to speed up the recovery of the industry in the wake of the pandemic. Although researchers have studied the impacts of pandemics in other industries in various settings, there is little-to-no research specific to the construction industry and especially in the Middle East region. To address this knowledge gap, 202 construction professionals in the Middle East region were surveyed using a questionnaire survey to provide their perceptions of COVID-19 pandemic impact on project finance, construction materials and equipment, labor, contracts, and rental properties. Statistical analysis of the collected data reveals that labor and contracts are the principal classes impacted due to the complex procedures of hiring labor from East Asia, the tightening of health and safety precautionary measures on construction sites, and the expected contract revisions to Force Majeure, Change, and Claim clauses to address pandemic issues. The respondents indicated that many tasks can be safely accomplished by remote work. They also indicated that pandemic-related slowdown can be detrimental to the construction industry; governments need to inject stimulus funding to help keep construction activity momentum; and prolonged COVID-19 pandemic impact would be harsher than oil price collapse. As such, this study contributes to the body of knowledge in construction management by studying the impacts of COVID-19 pandemic and providing construction industry stakeholders with lessons learned and recommendations to response strategies that can alleviate pandemic risks. [ABSTRACT FROM AUTHOR]

Airport expansion projects often require the presence of construction personnel, material, and equipment near airport secure areas/facilities, leading to an increase in the level of risk to airport security. Construction planners and airport operators need to carefully study this challenge and implement active measures in order to minimize construction-related security breaches and comply with all relevant Federal Aviation Administration guidelines. This paper presents the development of an advanced multiobjective optimization model for planning airport construction site layouts that is capable of minimizing construction-related security breaches while simultaneously minimizing site layout costs. The model incorporates newly developed criteria and performance metrics that enable evaluating and maximizing the construction-related security level in operating airports. The model is developed using a multiobjective genetic algorithm, and an application example is analyzed to demonstrate the use of the model and its unique capability of generating a wide spectrum of optimal trade-offs between construction-related airport security and site layout costs. DOI: 10.1061/(ASCE)0733-9364(2008)134:1(40) CE Database subject headings: Optimization; Evolutionary computation; Security; Airport construction; Site evaluation; Site preparation, construction; Construction management; Risk management.

Keratoconus is a progressive noninflammatory ectatic disease of the cornea with onset at puberty in most cases. Both genetic and nongenetic or environmental factors have been implicated. Keratoconus has been associated with numerous genetic systemic disorders. many keratoconus-associated syndromes have a high incidence of eczema and atopy, such as Down syndrome, hyper-IgE syndrome, ichthyosis, and oculodentodigital syndrome, Turner syndrome (conjunctival lymphangiectasia), autographism and Mulvihill-Smith syndrome. In each of these syndromes associated with atopy and eczema, associations are known to include both keratoconus and eye rubbing. Keratocyte density, possibly from IL-1-induced apoptosis, is reduced in keratoconus and can be demonstrated as well with eye rubbing and with contact lens wear. A recently developed treatment for keratoconus is corneal collagen crosslinking (CXL). In CXL, stromal fibers are photopolymerized by the combined action of a photosensitizing substance (riboflavin or vitamin B2) and ultraviolet rays A. [ABSTRACT FROM AUTHOR]

Construction operations in airport expansion projects often attract wildlife species to critical airport traffic areas leading to an increase in the risk of wildlife-aircraft collision accidents. Airport operators and construction planners need to carefully consider and minimize these wildlife hazards during the planning of construction site layouts in order to comply with Federal Aviation Administration recommendations. This paper presents the development of an advanced optimization model for planning airport construction site layouts that is capable of minimizing the hazards of wildlife attractants and minimizing the site layout costs, simultaneously. The model incorporates newly developed concepts and performance criteria that enable (1) quantifying, controlling, and minimizing the hazards of construction-related wildlife attractants near airport traffic areas; and (2) minimizing the travel cost of construction resources and the cost of devices installed to control wildlife on airport construction sites, while complying with all relevant aviation safety constraints. The model is developed using a multiobjective genetic algorithm and an application example is analyzed to demonstrate the use of the model in optimizing airport construction site layouts and its unique capability of generating optimal trade-offs between wildlife control and site layout costs. DOI: 10.1061/(ASCE)0742-597X(2006)22:4(176) CE Database subject headings: Optimization; Computation; Safety; Airport construction; Construction sites; Site evaluation; Site preparation; Wildlife.

Airport expansion projects often require the presence and movement of construction labor and equipment near critical airport traffic areas. This close proximity between construction activities and airport operations needs to be carefully considered during the planning of construction site layouts in order to minimize and eliminate all potential construction-related hazards to aviation safety. This paper presents the development of a multiobjective optimization model for planning airport construction site layouts that is capable of minimizing construction-related hazards and minimizing site layout costs, simultaneously. The model incorporates newly developed optimization functions and metrics that enable: (1) maximizing the control of hazardous construction debris near airport traffic areas; (2) minimizing site layout costs including the travel cost of construction resources and the cost of debris control measures on airport sites; and (3) satisfying all operational safety constraints required by the federal aviation administration as well as other practical site layout constraints. The model is implemented using a multiobjective genetic algorithm and an application example is analyzed to demonstrate the use of the model and its capabilities in optimizing construction site layouts in airport expansion projects. DOI: 10.1061/(ASCE)0733-9364(2006)132:6(562) CE Database subject headings: Optimization; Computation; Safety; Airports; Construction sites; Site evaluation; Site preparation, construction; Cost control.

Planning construction site layouts involves identifying the positions of temporary facilities on site, and accordingly it has a significant impact on the safety and efficiency of construction operations. Although available models are capable of minimizing the travel cost of resources on site, they do not consider safety as an important and separate objective in the optimization of site layouts. This paper presents the development of an expanded site layout planning model that is capable of maximizing construction safety and minimizing the travel cost of resources on site, simultaneously. The model incorporates newly developed concepts and performance criteria that enable the quantification of construction safety and travel cost of resources on site. The present model is developed in three main phases: (1) formulating decision variables and optimization objectives in this site layout planning problem; (2) identifying and satisfying all practical constraints in this optimization problem; and (3) implementing the model as a multiobjective genetic algorithm. An application example is analyzed to illustrate the use of the model and demonstrate its capabilities in optimizing construction site layouts and generating optimal trade-offs between safety and travel cost of resources on site. CE Database subject headings: Optimization; Evolutionary computation; Safety; Construction sites; Site evaluation; Site preparation; construction; Construction management; Cost control.

Copyright of Egyptian Journal of Botany is the property of Egyptian National Agricultural Library (ENAL) 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.)

Over the past few years there has been a significant change in fire safety design and management. As the possibility of safe escape is the most crucial aspect of a building's fire safety features, the understanding of human behaviour under fire conditions is important for a successful evacuation. Previous research studies have developed models, prototypes, and serious games that help engineers/architects to design or firefighters to improve design so that the building facilitates a smooth evacuation process. Although these studies have looked into human behaviour, perceptions of important stakeholders (such as occupants, structural engineers, fire engineers, facility managers) are still not understood. These perceptions are important for the appropriate application of technology for evacuation. The broader research effort, of which this paper is part, stems from the premise that bespoke evacuation instructions can be sent directly to evacuees' smartphones. Information from a BIM model with the aid of sensors can be used to customise these evacuation instructions. The prospect of information being delivered to occupants during a fire emergency is still at its premature phase and more research is needed. Twenty-three interviews were conducted with occupants who currently live in high-rise residential buildings in Egypt and the United Kingdom to understand their views of using smartphones to assist during fire evacuations. The sampling strategy targeted occupants who currently live in high-rise residential buildings but have not necessarily experienced a fire evacuation. The research clearly shows the importance of smartphones during evacuation and the role they can play in assisting occupants to find the fastest and safest egress route. The interview findings will assist in future research to develop an evacuation framework system that could be implemented for high-rise residential buildings. [ABSTRACT FROM AUTHOR]

Copyright of Egyptian Journal of Botany is the property of Egyptian National Agricultural Library (ENAL) 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.)

The growing demand for maritime transport imposes several challenges to port authorities, including reducing port congestion, planning for expansion projects, and allocating budgets for such capital projects. To address these construction planning problems, there is a vital need to identify the factors that influence port congestion and understand their impact on port expansion and reconstruction planning. This study focuses on: (1) identifying the decision variables that influence port expansion and reconstruction decisions; (2) modeling the impacts of these variables on the decision to expand a port; and (3) developing an automated system to forecast port expansion needs. The automated system employs a mixed-integer nonlinear programming model that is designed to predict port performance, given a projected increase in cargo demand. The developed model is empirically validated using real data acquired from Shuwaikh Port. For the projected 1.8% increase in cargo demand, it was concluded that the port will need expansion in 8 years. The present study contributes to the core body of knowledge of port construction engineering and management by providing a novel model and a practical automated system for projecting port expansion needs using real-time port data. This should prove useful to port authorities and construction planners as it facilitates the advancement of port construction planning, enhances port operational safety, and provides the capacity to predict port expansion and modernization needs. [ABSTRACT FROM AUTHOR]

The present study investigated the impact of cumulative irrigation with wastewater on the soil properties and, its health hazards on the consumers of cabbage plants at south Cairo Province, Egypt. Irrigation water, soil and cabbage plants were sample d from two polluted and other two unpolluted farms. The physicochemical properties of water and soil were analyzed and the growth parameters, as well as nutrients and heavy metals concentration in cabbage were investigated. In addition, the daily intake of metals (DIM) and health risk index (HRI) were estimated. Wastewater posed a decrease in the availability of N, P and K, but increases heavy metals in the soil solution. Cabbage stem and root lengths as well as the number of leaves and biomass were greatly reduced in the polluted farms. In addition, the photosynthetic pigments, carbohydrates and proteins were decreased under pollution stress. The concentration of most investigated metals in the leaves and roots were increased with translocation factor greater than one for Pb, Cd, As, Cr, Ni, Fe, and Co. The study revealed that the HRI exceeded one for Pb and Cd in polluted and unpolluted plants; and Fe in polluted ones. Irrigation with wastewater is not suitable for cabbage as it has health risks on humans due to accumulation of heavy metals. It worth noting that, the high ability of cabbage plants to accumulate Pb and Cd from both polluted and unpolluted soils should be taken into consideration when consuming this plant. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this article is to evaluate and compare the outcomes of simultaneous and successive femtosecond laser-assisted intrastromal corneal kera-ring segments insertion and corneal collagen cross-linking in the treatment of keratoconus. [ABSTRACT FROM AUTHOR]

Abstract: Desalination of seawater has become an important and growing field due to the present water shortage in some countries. This activity may result in some environmental impacts, mainly generated by the discharge into the sea of the brine produced, which can affect marine benthic communities. The present study aims to study the response of the seagrass Halodule uninervis (Forssk.) Aschers. to hypersaline stress. The results showed that H. uninervis fully tolerate salinity up to 50psu by accumulation of the organic osmoprotactants (free amino acids, proline and soluble sugars) and inorganic osmoprotactants specially Na+ and K+. Sublethal effects appeared at 55psu and the plants fully recovered when returned to normal salinity. Salinities 60 and 65psu have a drastic effect on this seagrass and the plants did not recover after returning to the normal conditions. The results indicated that H. uninervis can tolerate salinity above control by 15psu. To conserve this plant, it is recommended that the brine must be diluted at least to 50psu before discharging it into the sea. [Copyright &y& Elsevier]

In nonlinear construction optimization problems, the capability of current optimization algorithms to find an optimal solution is usually limited by their inability to evaluate the effects of changing the value of each decision variable on reaching the optimal solution. This paper presents fundamental research aimed at developing a novel evolutionary optimization algorithm, named Electimize, that mimics the behavior of electrons flowing, through electric circuit branches with the least electric resistance. In the proposed algorithm, solutions are represented by electric wires and are evaluated on two levels: a global level, using the objective function, and a local level, evaluating the potential of each generated value for every decision variable. The paper presents (1) the research philosophy and scope, (2) the research methodology, and (3) the development of the algorithm. The proposed algorithm has been validated and applied successfully to an NP-hard cash flow optimization problem. The algorithm was able to find a better optimal solution and identified ten alternative optimal solutions for the same problem. This should prove useful in enhancing the optimization of complex large-scale problems. [ABSTRACT FROM AUTHOR]

In building construction, contractors are typically selected through competitive bidding or negotiated contracting, in which the project price is the major selection criterion. A contractor's safety performance is still not a major selection criterion, despite the existence of numerous safety prequalification methods. The negative repercussions of such apathy create a critical need for systems that enable owners to evaluate contractor safety performance and facilitate the selection of safety-conscious contractors by virtue of their good safety practices. This study presents the development of a computerized platform for evaluating contractor safety performance that is capable of analyzing contractors' safety performance data. The platform incorporates newly developed parameters that enable (1) including leading and lagging safety indicators that depict current and past contractor safety performance; (2) conducting analysis on both the organizational and project levels; and (3) satisfying the requirements of international safety standards. This research contributes to the existing body of knowledge by presenting a validated standard-compliant set of 10 indicators and 71 metrics that facilitate evaluating contractor safety performance and establishing their significance analytically. This should prove useful to decision makers and researchers alike and is a step forward to facilitate including contractor safety performance among major selection criteria, which can ultimately bring significant improvements to the building industry's safety. [ABSTRACT FROM AUTHOR]

Abstract: Juniperus phoenicea L. is listed as threatened tree by IUCN Red List. In Egypt, J. phoenicea L. is the only conifer tree that is restricted to the three mountains of northern Sinai: Gabal El-Halal, Gabal El-Maghara and Gabal Yelleq. As a Mediterranean relict it has been included in a national list as target for conservation and management. To provide baseline information for the development of a conservation strategy, the present study aims at comparing the isolated populations of J. phoenicea and their associated plant composition and diversity at the three mountains. The application of TWINSPAN and DCA analysis techniques has resulted in identifying of four vegetation types associated with juniper, and each could be related to a specific geomorphologic habitat on a topographic gradient. Chiliadenus montanus and Zygophyllum dumosum characterized the slopes of smooth-faced rock outcrops in Wadi Abu Seyal (at 350–470m altitude of Gabal El-Halal), Deverra tortuosa, Ephedra aphylla and Gymnocarpos decander inhabited together with the target species the soil pockets of north-facing slope in Neqeb Abu Hamam (at 600–700m altitude of Gabal El-Halal), Stachys aegyptiaca and Moricandia nitens characterized the juniper occurrences in the runnels of Wadi Arar (at 450–560m altitude of Gabal El-Maghara), and Artemisia herba-alba, Atriplex halimus and Reaumuria hirtella represent the stands on slope runnels (at 900–960m) of Gabal Yelleq. The two vegetation types recognized at Gabal El-Halal had, on average, the highest species diversity, juniper density and cover. Juniper shows generally poor conditions of vitality at higher elevation (600–960m) with a higher proportions of old and recent dead trees, and with the predominance of male individuals, as compared with the populations of Gabal El-Maghara and Gabal Yelleq. In contrast, the juniper populations at lower elevation (350–470m) of Gabal El-Halal proved to be in best condition with mostly living foliage and reproductive branches. The differences in rock types and elevation among the three mountains reflect serious limitation on recruitment of J. phoenicea due to moisture availability. The results of this study showed that J. phoenicea is an endangered species and its conservation in northern Sinai mountains is a priority. For a successful conservation of this community it is highly recommended to preserve in particular the suitable habitats at Gabal El-Halal, but also the other stands merit conservation measures. [Copyright &y& Elsevier]