Top PDF Evaluation of Common Maintenance Methods for Flexible Pavements

Evaluation of Common Maintenance Methods for Flexible Pavements

Evaluation of Common Maintenance Methods for Flexible Pavements

Abstract: Problem statement: With the increasing use and awareness of pavement management systems and the growing emphasis on asset management of pavement infrastructure, it is important to strengthen the maintenance components of these systems and particularly the preventive maintenance component. Iraqi roads don’t receive an effective and proper maintenance during their service life until they reach the state of major failure that requires rehabilitation. Roads in Iraq are being lost. Approach: In this study, a study of the status of maintenance methods for road pavements in Iraq with special reference to flexible pavements was presented. For this purpose, open and closed questionnaires were executed in Baghdad to investigate the status of road pavement maintenance in Iraq. Road maintenance offices as (Ministry of construction and Housing, State Corporation for Roads and Bridges, Amanat Baghdad, Project office,) were included in the questionnaire to arrive at the level of maintenance and techniques followed to maintain paved road in Iraq. Results: The interviews carried out reveal that maintenance in Iraq has secondary importance, apparently with no special budget allocated for such important works. In addition the maintenance methods and techniques followed do not comply the developments and modern techniques. Conclusion/Recommendations: Poor and miss-management of maintenance works and activities leading to delays and accumulation of failure in the highway network that require unusual expenditures to repair and maintain the accumulated damages. Shortages in resources allocated for maintenance works and this leads to the diversion of significant portion of the allocated fund for maintenance works toward purchasing of new, or additional equipment to be used for the construction of new roads. It is strongly recommended to design a planning system for management pavement maintenance of road network in Iraq and develop a particular failure criterion for roads in Iraq.
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eve asholanda Finite Element Modeling of Flexible Pavements

eve asholanda Finite Element Modeling of Flexible Pavements

The Control class provides a common interface for the global algorithms used to analyze a problem. Currently, it is composed of four subclasses: LinearStatic, EquilibriumPath, QuasiStatic and LinearNewmark. The Node class basically stores the nodal data read from the input file (coordinates, support conditions, etc.), as well as some variables computed during the program execution, as the nodal degree of freedom and the current displacements. It also provides a number of methods to query and to update the stored data. The Element class defines the generic behavior of a finite element. The main tasks performed by an object of the Element class are the indication of the number and direction of the active nodal d.o.f., the computation of the element vectors (e.g., internal force) and matrices (e.g., stiffness matrix), and the computation of the element responses (e.g., strains and stresses). The Shape class holds the geometric and field interpolation aspects of the element (dimension, topology, number of nodes, nodal connectivity, and interpolation order).
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Rigid Pavements Distresses - Pavement Condition Index Evaluation

Rigid Pavements Distresses - Pavement Condition Index Evaluation

The PCI evaluation assesses the condition of the pavements based on distresses observed and does not include tests for structural or functional measurement of these characteristics. Nevertheless when performed systematically, it provides an indication of pavement condition evolution in time. This evaluation procedure has widespread acceptance not only in North America but also throughout the world due to reduced costs. While the methodology enables trained and experienced inspectors to gather consistent and repeatable data pertaining to the pavement system, there are limitations to the procedure, particularly when the collected data are used in pavement maintenance programs (PMP). Nevertheless, due to the fact that is a visual inspection procedure, there are some common misapplications that need to be addressed such as subjectivity in the distress evaluation or the fact that the structural condition cannot be assess directly. With few adjustments, some of these limitations can be overcome, making the PCI procedure even more valuable. Some of those limitations can be reduced, such as the subjectivity of the PCI calculation due the abacus consultation and others improved with the introduction of structural condition evaluation.
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MATERIALS AND METHODS Microorganism maintenance and culture conditions

MATERIALS AND METHODS Microorganism maintenance and culture conditions

Enzyme application in biotechnological and environmental processes has had increasing interest due to its efficiency, selectivity and mainly for being environmentally healthful, but these applications require a great volume of enzymes. In this work the effect of different concentrations of ethanol and 2,5 xylidine on growth and production of laccase by was investigated. In a medium containing 200 mg.L 1 of 2,5 xylidine or 50 g.L 1 of ethanol, the maximum activity of laccase was 2019 U.L 1 and 1035 U.L 1 , respectively. No direct correlation between biomass and activity of laccase was observed for any of the inducers used during the tests. Ethanol concentrations, larger than or equal to 20 g.L 1 , inhibited the radial growth of . This study showed that ethanol, which has less toxicity and cost than the majority of the studied inducers, presents promising perspectives for laccase production by
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Performance evaluation of waste stabilization pond in Birjand, Iran for the treatment of municipal sewage

Performance evaluation of waste stabilization pond in Birjand, Iran for the treatment of municipal sewage

Assessment of wastewater treatment processes demonstrate that the stabilization ponds is the most simple, reliable, economical and low maintenance process that can be used as an appropriate alternative for wastewater treatment and ponds are systems that effectively stabilize wastewater by reducing BOD (Wiley et al., 2009; Mozaheb et al., 2010). Wastewater treatment in stabilization ponds reaches to its maximum with proper selection of organic load, time and depth of the pond and atmospheric conditions for maximum growth of microorganisms (Khosravilaghab et al., 2009). Waste stabilization ponds in most cities in Iran are valuable treatment systems due to suitable climatic conditions and land availability (Ehrampoush et al., 2007).Waste stabilization pond is divided into three types based on type of biological activity occurring in a pond. Three types are renowned: anaerobic, facultative and maturation ponds, anaerobic and facultative ponds are employed for BOD removal, while the primary function of maturation pond is to remove excreted pathogens (Gawasiri, 2003).
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RATES AND METHODS OF APPLYING UREA TO COMMON BEANS

RATES AND METHODS OF APPLYING UREA TO COMMON BEANS

The results observed for the crop in the Red-Yellow Latosol, as regarding the methods of applying urea, were confirmed in the Solodic Planosol, as the yields obtained when the fertilizer[r]

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Research advances in theories and methods of community assembly and succession

Research advances in theories and methods of community assembly and succession

Community succession is a phenomenon or process by which an ecological community undergoes more or less orderly and predictable changes following a disturbance or initial colonization of new habitat (Connell and Slatyer, 1977). It is the observed process of change in the species structure of an ecological community over time. The community begins with relatively few pioneering plants and animals and develops through increasing complexity until it becomes stable or self-perpetuating as a climax community (Wikipedia: http://en.wikipedia.org/wiki/Ecological_succession; Fig. 2). In general, succession is composed of three phases: (1) invasion and colonization. Some pioneer species invade and colonize in the barren land, change the environment, and thus lay basis for successive invasions of other species. (2) Competition and equilibrium. Some species survive in the competition and some species extinct. The coexisting species reach an equilibrium state in utilizing resources. (3) Relatively stable state. Species composition and abundance are relatively fixed. Food web is complex and stable. However, so far there is not widely recognized pattern and theory on community succession (Lebrija-Trejos et al., 2010).
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MATERIALS AND METHODS Organism, maintenance and culture conditions

MATERIALS AND METHODS Organism, maintenance and culture conditions

A Penicillium purpurogenum strains, isolated in our laboratory, was found to produce both extracellular and intracellular fructosyltransferases, the present paper reports the results of optimization of constituents in the culture medium and environmental parameters like cultivation time, initial pH, temperature, carbon source for maximum fructosyltransferase production. The effect of sucrose feeding to the cultivation medium when sucrose was completely exhausted was also monitored.

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WITHDRAWAL OF MAINTENANCE THERAPY FOR CYTOMEGALOVIRUS RETINITIS IN AIDS PATIENTS EXHIBITING IMMUNOLOGICAL RESPONSE TO HAART

WITHDRAWAL OF MAINTENANCE THERAPY FOR CYTOMEGALOVIRUS RETINITIS IN AIDS PATIENTS EXHIBITING IMMUNOLOGICAL RESPONSE TO HAART

On day 120 of follow-up, Patient A presented progressive polyradiculopathy and typical CMV retinitis that led to a clinical diagnosis of CMV disease, despite negative antigenemia tests and negative PCR results performed on the cerebrospinal fluid. After ganciclovir treatment, this patient recovered completely. Lymphoproliferative assays were negative, indicating the absence of a specific response to CMV. The CD4+ count at the time of recurrence was 195 cells/mm 3 .

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MATERIAL AND METHODS Microorganisms and its maintenance

MATERIAL AND METHODS Microorganisms and its maintenance

Sodium acetate acts as a buffering agent and helps to maintain the pH in the fermentation process (Kim et al., 2003). Sodium acetate was used in the medium to study its effect on glucansucrase and glucan production. At lower concentration (0.05%, w/v), it did not have any effect on glucansucrase as well as glucan production (Fig. 4, Table 1). However, beyond 0.05% concentration sodium acetate negatively affected both. Whereas, Sawale and Lele (2010) reported positive effect of sodium acetate (1.51% w/v) on dextransucrase and dextran production by a Leuconostoc mesenteroides strain isolated from fermented idli batter.
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MATERIALS AND METHODS Organism, Growth and Maintenance

MATERIALS AND METHODS Organism, Growth and Maintenance

Both enzymes can be produced economically and profitably on a large scale through fermentation process using a specific and potent strain. Submerged as well as solid-state fermentation techniques are used for the production of proteases and alpha amylases; however, bacteria usually give higher yields through submerged fermentation. A new trend in fermentation technology has arrived which is the simultaneous production of two or more products. In this technique, more than one product is produced by a single microorganism in a single fermentation batch under same or different conditions. Several workers have used this technique and have successfully produced more than one product simultaneously in a single batch operation (27, 10, 5, 25). This is a successful fermentation technique by which time, labor and energy can be saved and fermentation batches can be economized for maximum outputs from minimum inputs.
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 Glimpses for Effective implementation of  Virtual Trainer

Glimpses for Effective implementation of Virtual Trainer

E learning is a process of using multimedia technology and the Internet technology to improve the quality of learning in education. Multimedia technology allows the use of movie, audio and text resources to enrich the contents. Internet technology allows accessing the resources and services easily and effectively. E learning stimulates remote exchanges and collaboration. E learning empowers the learner in various situations in learning at schools, learning at university, learning at work and learning at home. E learning plays a fundamental role in developing web based training system for the implementation of Virtual trainer
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MATERIALS AND METHODS Microorganism and culture maintenance

MATERIALS AND METHODS Microorganism and culture maintenance

1. The independent and the dependent variables were fitted to the second-order model equation. They were examined in terms of the goodness of fit. Furthermore, the analysis of variance (ANOVA) was used to evaluate the adequacy of the fitted model. The R-square (correlation coefficient) value provides a measure of how much of the variability in the observed response values could be explained by the experimental factors and their interactions. A good model explains most of the variations in the response. The closer the R-square value is to 1.0, the stronger the model and the better are the response predictions. On the basis of the ANOVA, as shown in Table 5, a second order model (Equation 3) was estabilished, describing the enzyme activity as a function of SCM, CSL and YEP concentrations. The pure error was very low, indicating a good reproducibility of the experimental data. Based on the F test, the model is predictive, since its calculated F value is higher than the critical F value and the regression coefficient is close to unity. The coded model was used to generate response surfaces and contour curves (Figs. 2 and 3) for the analysis of the variable effects on glucosyltransferase activity:
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MATERIALS AND METHODS Organism, maintenance and culture condition

MATERIALS AND METHODS Organism, maintenance and culture condition

Many bacteria, fungi and yeast have been shown to produce the enzyme ß-glucosidase. The bacteria like Bretlanomyces bruxellensis (11), Oenococcus oeni (11) and Clostridium thermocellum (7), the fungi like Aspergillus oryzae (16), Fusarium oxysporum (2), Trichoderma reesei (19), and the yeasts like Candida peltata (18), Candida curvata (20) are also reported to be the main producers. Penicillium purpurogenum is among the few fungi, which produced intracellular ß-glucosidase. The objective of the present investigation was to optimize the cultural parameters for maximum production of ß-glucosidase by P. purpurogenum. Effect of initial pH, agitation and different carbon sources on enzyme production has been studied. The effect of additives
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Evaluation of common bean accesses with multi-category variables

Evaluation of common bean accesses with multi-category variables

Querol (1993) reported that the botanical characterization of germplasm identified and differentiated the phenotypes of the varieties, preventing the duplication of accesses within the collection. They thus used descriptions with high heritability, easy identification and expressions in all environments. The agronomical describers were of low heritability, even desirable to the producer. They had to visualize adaptation of the material and its productive potential, placing in evidence promising genotypes and their use in improvement programs.

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Braz. Dent. J.  vol.17 número1

Braz. Dent. J. vol.17 número1

It is mandatory to be open-minded to question the paradigms that involve our profession, because whenever a paradigm acquires an extraordinary impact over those who adhere to it, it may become an indubitable belief. In the majority of the times, such adherence may create a strong connection, which leads both clinicians and researchers to admit solely their own theory, for it seems evident to them that there is no other way to be. It constitutes the so-called settlement of the paradigm. In Endodontics, a paradigm has been created. Theories and techniques for instrumentation of curved root canals state that the use of a #25 file in the apical portion fulfills all the requisites for cleaning and shaping of the root canal system. The theories emphasize that, beyond this numbering (#25), failures such as deviations, perforations, zipp, etc, may occur frequently (2-5).
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Application of time-series analysis for prediction of molding sand properties in production cycle

Application of time-series analysis for prediction of molding sand properties in production cycle

All data used in the present work have been obtained from a Polish grey cast iron foundry, equipped with two Disamatic molding lines (2110 Mk3 and 2110 Mk5 with a sand cooling system. The original source data included 624 records collected during three summer months, in 39 working days (16 records per day in 1 hour intervals). The following green sand properties were measured and recorded: moisture content of used and fresh sands, compression strength, permeability, compactibility, and temperatures of used and fresh sands.

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Rev. LatinoAm. Enfermagem  vol.22 número1

Rev. LatinoAm. Enfermagem vol.22 número1

Objective: to evaluate the conformity of the assistential practice in the maintenance of the temporary double-lumen catheter for hemodialysis, by means of the use of the process indicator, in the University Hospital of the University of São Paulo. Method: a quantitative, exploratory- descriptive and observational study. The sample was made up of 155 observations of persons with temporary double-lumen catheters, in the period March – November 2011, using the Indicator of the Maintenance of the Temporary Double Lumen Catheter for Hemodialysis. Results: the rate of general conformity of the assistential practice corresponded to 65.8%. Of the practice’s 13 components, 9 (69.2%) attained 100% conformity. The hygienization of hands by the professionals and the use of a mask by the patients during the disconnection from the hemodialysis had the worst rates (83.9%). Conclusion: although the actions evaluated are implemented in the unit, it is necessary to propose and apply educational strategies with the health team, as well as to institute periodical assessments, so as to raise the conformity rates, ensuring the quality of the hemodialysis services.
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Establishment and evaluation of flexible insect cell lines for rapid production of recombinant proteins

Establishment and evaluation of flexible insect cell lines for rapid production of recombinant proteins

The insect cell/baculovirus infection system is a preferred platform for the production of recombinant proteins due to its eukaryotic protein processing capabilities and relatively short process development timelines. However, the lytic nature of virus infection can negatively impact final product quality and increase the challenges of the downstream process. Therefore, the main motivation of this work was to develop an alternative platform to the infection system that would likewise explore and benefit from the manufacturing potential of insect cells. The adopted strategy relies on recombinase cassette exchange (RMCE) technology to enable flexible and fast establishment of production cell lines. This technology consists in tagging randomly the cell genome with a reporter gene and screen for high expressing loci and then, to re-use these loci for expression of different proteins of interest. The recombination system implemented in Sf9 cells for the first time in the scope of this thesis was based on the yeast- derived Flipase (Flp) recombinase, which promotes recombination between Flp recognition target sites. The proof of concept was performed with reporter proteins. The identification of clones tagged in loci supporting Flp-mediated recombination allowed their re-use for expression of EGFP at levels correlated to those of the red reporter protein previously encoded in the corresponding loci. The best RMCE-Sf9 cell line was evaluated regarding the production of complex proteins, namely rotavirus core-like particles. Albeit lower cell specific productivities with respect to those presented by baculovirus infection, the protein titers achieved were comparable. Furthermore, a fluorescence-activated cell sorting protocol was developed enabling to sort high-expressing dsRed-tagged Sf9 and High Five cells, contributing to speed up RMCE-based cell line development. Overall, the developed RMCE-insect cell lines represent powerful platforms for fast production of recombinant proteins.
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Evaluation of alternative methods for the disinfection of toothbrushes

Evaluation of alternative methods for the disinfection of toothbrushes

Abstract: The aim of this study was to evaluate alternative methods for the disinfection of toothbrushes considering that most of the previous- ly proposed methods are expensive and cannot be easily implemented. Two-hundred toothbrushes with standardized dimensions and bristles were included in the study. The toothbrushes were divided into 20 ex- perimental groups (n = 10), according to microorganism considered and chemical agent used. The toothbrushes were contaminated in vitro by standardized suspensions of Streptococcus mutans, Streptococcus pyo- genes, Staphylococcus aureus or Candida albicans. The following dis- infectants were tested: 0.12% chlorhexidine digluconate, 50% white vinegar, a triclosan-containing dentifrice solution, and a perborate-based tablet solution. The disinfection method was immersion in the disinfec- tant for 10 min. After the disinfection procedure, the number of remain- ing microbial cells was evaluated. The values of cfu/toothbrush of each group of microorganism after disinfection were compared by Kruskal- Wallis ANOVA and Dunn’s test for multiple comparisons (5%). The chlorhexidine digluconate solution was the most effective disinfectant. The triclosan-based dentifrice solution promoted a signiicant reduction of all microorganisms’ counts in relation to the control group. As to the disinfection with 50% vinegar, a signiicant reduction was observed for all the microorganisms, except for C. albicans. The sodium perborate solution was the less effective against the tested microorganisms. Solu- tions based on triclosan-containing dentifrice may be considered effec- tive, nontoxic, cost-effective, and an easily applicable alternative for the disinfection of toothbrushes. The vinegar solution reduced the presence of S. aureus, S. mutans and S. pyogenes on toothbrushes.
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