Behavior characterization and development of LRFD resistance factors for axially-loaded steel piles in bridge foundations

The Federal Highway Administration (FHWA) mandated utilizing the Load and Resistance Factor Design (LRFD) approach for all new bridges initiated in the United States after October 1, 2007. Consequently, significant efforts have been directed by Departments of Transportation (DOTs) in different states towards the development and implementation of the LRFD approach for the design of bridge\u27s deep foundations. The research presented in this thesis is aimed at establishing the LRFD resistance factors for the design of driven pile foundations by accounting for local soil and pile construction practices. Accordingly, regional LRFD resistance factors have been developed for different static analysis methods, incorporating more efficient in-house and combinations of suitable pile design methods, following the AASHTO LRFD calibration framework. Typical calibration framework was advanced in the research presented in this thesis to incorporate the effects of layered soil systems and to reduce the uncertainties associated with soil variation along pile embedment. To achieve the calibration process successfully, the following three major tasks were accomplished as part of the research presented here: (1) completion of nationwide and statewide surveys of different state DOTs and Iowa county engineers, respectively, to obtain necessary information regarding current pile design and construction practices, the extent of LRFD implementation and regional calibration, as well as to learn of existing local practices; (2) calibration of the LRFD resistance factors for bridge deep foundations, based on the local database (PIle LOad Tests in Iowa [PILOT-IA]), was developed as part of the project and contained data from 82 load-tested steel H-piles, as well as adequate soil profile information; and (3) conduction often full-scale instrumented pile static load tests that cover different local soil regions, accompanied by various soil in-situ tests, including standard penetration test (SPT), cone penetration test (CPT), borehole shear test (BST), and push-in-pressure-cells, in addition to soil laboratory tests with soil classification, 1-D consolidation, CU-Triaxial tests, and direct shear test (DST). In addition, the AASHTO LRFD calibration framework only addresses pile design at the strength limit state; however, more comprehensive and practical design recommendations should account for the strength and serviceability limit states, simultaneously. For this purpose, two different levels of advanced analysis to characterize the load-displacement response of piles subjected to axial compressive loads were used. The first level of analysis was based on an improved load-transfer method (or t-z model), attained as follows: (a) establishing a modification to the Borehole Shear Test equipment (mBST), that, for the first time, allows for a direct field measurement of the soil-pile interface properties for clay soils; (b) establishing a modification to the Direct Shear Test (mDST), that allows for an accurate and simple laboratory measurement of the soil-pile interface for sands; and (c) adapting a new Pile Tip Resistance (PTR) laboratory test that can measure practically the pile end-bearing properties. The improved t-z analysis uses the measured soil-pile interface properties from the mBST and/or the mDST for different soil layers, and also uses the end-bearing properties of the soil under the pile tip from the PTR laboratory measurements. The t-z analysis showed significantly improved characterization for the pile load-displacement behavior and load distribution along the pile length, compared to field test results. The second level of analysis was based on finite elements (FE), where the Mohr-Coulomb soil constitutive properties were adjusted, using a sensitivity analysis based on various laboratory soil tests, such as the mDST and CU-Triaxial tests. After improving the reliability of the different analytical models in characterizing the behavior of axially-loaded steel piles, a new LRFD displacement-based pile design approach was provided in this thesis, utilizing the improved analytical models

IL-13 R130Q single nucleotide polymorphism in asthmatic Egyptian children

Background: Asthma and its associated phenotypes are under a substantial degree of genetic control. The common variant IL-13 gene polymorphism R130Q is reported to be associated with the risk of development of asthma in some populations. Objective: We sought to study the association of IL-13 genetic variant R130Q with bronchial asthma in Egyptian children and its relation to various clinical and laboratory phenotypes of the disease. Methods: IL13 gene polymorphism (R130Q) was detected by PCR amplification followed by sequencing using pure script total DNA in 20 asthmatic patients in acute exacerbation. The results were compared to 20 healthy age and sex matched children. Results: Asthmatic children had significantly higher frequency of distribution of R130Q genotype (50%) than controls (15%). The serum total IgE as percent of high normal for age was significantly higher in asthmatic patients as compared to controls with a mean of 208.77 ±237.06% and 14.21 ± 8.08% respectively. No significant difference was observed in the mean AEC(as a percent of high normal for age) of both groups (80.85 ± 116.4% and 82.50 ± 81.4% respectively). No significant differences were observed between patients with IL-13 polymorphism R130Q and those without such polymorphism as regards family history, relation of exacerbations to upper respiratory tract infections, history of food allergy or asthma grading. Serum total IgE was significantly higher in asthmatics with GA genotype as compared to those with GG genotype with a mean of 373.25 ± 238.11% and 44.28 ± 42.65% respectively. A similar finding was also observed among the control group with a mean of 28.03 ± 9.12% and 11.77 ± 5.00% respectively. Finally a significantly higher AEC was observed in controls with GA as compared to GG genotype with a mean of 250.00 ± 51.96% versus 52.94 ± 36.87% respectively. Conclusion: The common variant IL-13 gene polymorphism R130Q is frequently associated with pediatric asthma. This variant is more active than the wild type in inducing allergic inflammation as reflected by the higher serum total IgE and AEC. Hence, IL-13R130Q may be candidate for future gene therapy targeted at reducing the ill-effects of this polymorphism.Keywords: IL-13R130Q – bronchial asthma - pediatricsEgypt J Pediatr Allergy Immunol 2010;8(1):9-1

Market risk management in Islamic finance : an economic analysis of the rationale, permissibility and usage of derivative hedging instruments

The examination of the topic of market risk management in Islamic finance is a complex endeavour. At a basic level, the subject matter, being multifarious in a manner that mixes religion and economics, requires the conjoining of religious faith with scientific objectivity in order to ascertain the truth contained in the scripture as it pertains to the Mua’amalat (dealings between individuals) matter of entering into financial contracts with others to manage market risk exposures. Moreover, the complexity is compounded due to the need to disentangle the ambiguity that has beset the discourse on the topic due to historically being mostly legal-centric with a focus on debating the contractual elements rather than attempting to comprehensively address the myriad issues that relate to market risk management in contemporary contexts. These issues, for the most part, revolve around the reliance on market risk transfer as a strategy and derivative contracts, with monetary underlying variables, as tools to implement that strategy. Thus, the journey of investigating the rationale, permissibility, and usage of derivative hedging instruments for market risk management in Islamic finance is, essentially, an undertaking that seeks to engage in a wide-ranging and multi-layered examination of the subject matter as well as the exploration of new areas of relative significance. This, in turn, and subsequent to the analysis of data generated from documentary sources and forty-one interviews which were collected from numerous sources within four locations, led to the elaboration of the contention that market risk management through derivative instruments for legitimate hedging purposes should not be prohibited in the Shari’a, albeit with certain conditions that limit unproductive behaviour. The basis for the aforementioned contention is built on the fact that market risk management has undergone a paradigm shift in how exposures are identified and measured as well as in the emergence of innovative tools which can result in a better ability to address the opportunities and challenges facing institutions that provide value to society (i.e., the real sector). Moreover, there is little substantive evidence that proves that the utilization of derivative instruments for hedging purposes leads its users to partaking in transactions that circumvent the prohibition of Riba (usury), Gharar (excessive uncertainty), and Maysir (gambling). In effect, the derivative instruments used for the management of market risks are not only disassociated from usurious debt transactions, they are also transacted in the financial markets in a manner that is transparent to all the parties involved. Along the same lines, the prohibition of Maysir, which is apparently an overarching concern, should be conceptualized with the focus on the proscription of the act of gambling, not necessarily the instruments (e.g., derivatives) and/or any particular framework (e.g., zero-sum arrangements). Ultimately, one should be cognizant of the fact that the true intentions of Islamic jurisprudence in Mua’amalat (as a manifestation of divine guidance) always centre on human well-being. Accordingly, the religious prohibitions are, in essence, within the realm of acts that adversely affect human well-being. This is a constant theme that is present throughout the thesis; and is one that exists at the heart of a wider aspiration of its adoption to a greater extent than is currently present in the Islamic finance discourse

STR-832: ULTIMATE FLEXURAL STRENGTH AND LONG-TERM CREEP DEFLECTION FOR STRUCTURAL INSULATED FOAM-TIMBER SANDWICH PANELS

The structural insulated panel (SIP) is a sandwich structured composite that is prefabricated by attaching a lightweight thick core made of Expanded Polystyrene (EPS) foam laminated between two thin, and stiff face skins made of Oriented Strand Board (OSB). The use of sandwich panels provides key benefits over conventional materials including: very low weight; high stiffness; durability and; production and construction cost savings. The facing skins of the sandwich panel can be considered as the flanges for the I-beam carrying bending stresses in which one face skin is subjected to tension, and the other is in compression. The core resists the shear loads and stabilizes the skin faces together giving uniformly stiffened panel. OSB is wood product that shrinks when dry and swells when adsorb moisture either due to liquid or vapor from the surrounding atmosphere. The relative combination of relative humidity and temperature is introduced into the equilibrium moisture content (EMC) that increases with the increase of the relative humidity and with decreasing temperature. Experimental test matrix includes testing 2.44 m (8’) and 4.88 m (16’) long SIPs for 5 years under different sustained loads and weather resistive barriers (WRBs), recording creep deflection, relative humidity and temperature. After creep recovery, the SIPs are loaded to-collapse to determine their flexural strength

Preparation and characterization of starch /cellulose composite

Novel preparative method for starch/cellulose composite in different ratios has been reported. The composite is obtained by mixing cellulose extracted from paper garbage and corn starch in PEG/NaOH solution. Starch/cellulose composite is characterized by different techniques, namely XRD, TGA and optical absorption measurements. From XRD data, it is observed that cellulose would lead to expand the d-spacing of (1ī0 plane and decrease the d-spacing of (110) plane of starch. The UV absorption peaks are shifted towards the longest wavelengths in the visible region for starch/cellulose composite. However, the refractive index value decreases from 1.44 to 1.08 and consequently the dielectric constant value decreases from 2.07 to 1.16 with increasing the starch ratio. Furthermore, the glass transition temperature increases from 107 °C for starch to 115 °C for starch/cellulose composite. However, the excess in starch ratio leads to increase in local crosslink density in the composite network

4-Hydroxy-2-methyl-N-(2-thiazole)-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide (EX15) and its Cu(II) Complex as New Oxicam Selective Cyclooxygenase-2 Inhibitors

4-Hydroxy-2-methyl-N-(2-thiazole)-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide (EX15) as nonsteroidal antiinflammatory drug (NSAIDs) of oxicam family has been synthesized bearing high se-lectivity for cyclooxygenase-2 (COX-2) inhibition and high ability to chelate with Cu(II) ions. The EX15-Cu(II) complex, and [Cu(EX15)(OAc)(H2O)2], were synthesized and characterized by using elemental analysis, spectral (UV-Vis, IR), conductance, thermal and magnetic studies. Two equations were predicted using quantitative structure activity relationship (QSAR) and regression analysis for the COX-2 and COX-1 selectivity (microsomal assay) with a regression correlation (R) close to unity. Two techniques were used to investigate the validity of these equations; macrophage cell line (in vitro) selectivity and collagen-adjuvant arthritis model in rats (in vivo) which showed a significant antioxidant, analgesic and antirheumatic effect for 4-hydroxy-2-methyl-N-(2-thiazole)-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide and its Cu(II) complex, [Cu(EX15)(OAc)(H2O)2]. (doi: 10.5562/cca1802

Tuning tetracycline removal from aqueous solution onto activated 2:1 layered clay mineral: Characterization, sorption and mechanistic studies

© 2019 Elsevier B.V. Water pollution due to emerging contaminants (especially pharmaceuticals) is a major environmental threat which results in the development of antibiotic-resistant bacteria/resistance genes in the aquatic environment. Therefore, robust and cost-effective methods are required to address this problem. In this study, thermal activation was opted for the modification of natural bentonite clay (BC) and utilized to investigate the adsorptive removal of tetracycline (TC) from aqueous solution. The physicochemical surface properties of the raw and modified bentonite samples were also investigated. The BET analysis revealed that the thermally activated bentonite (TB) has better properties than BC. The surface area of TB was found to be more than two-fold higher compared to that of BC. The FTIR spectra exhibited the existence of Al[sbnd]OH, Si[sbnd]O and Si[sbnd]O[sbnd]Si functional groups in the samples, confirming the presence of hydrated aluminosilicate in the clay. The effects of various operating parameters were analyzed via optimization studies. The maximum monolayer adsorption capacity estimated by Langmuir model was found to be 156.7 and 388.1 mg g−1 for BC and TB, respectively. Furthermore, fixed-bed column studies were performed to get insights into the adsorption behavior of TB in a dynamic system. The mechanism of TC adsorption by TB was successfully explored

The nature of the inferior ovary in some monocotyledonous families

The floral vasculature aspects of twenty-four species belonging to six monocotyledonous families are dealt with. These selected taxa include 23 horticulture species cultivated in Egypt and the remainders is among the wild flora of Egypt. A great attention has been focused by phylogenetists on the position of the ovary with respect to the other parts of the flower. In this connection, the nature of the inferior ovary is generally discussed on the basis of two theories; appendicular and axial. It is fortunate that the vascular skeleton can still be regarded as the most conservative character and that it may be rather conclusive in the determination of the nature of the inferior ovary. In the present study, the different patterns of floral vascularization are presented in cumulative tables and figures to facilitate the comparative study. Moreover, an interpretation to the observed variations is also tried to reach at the relations between the taxa studied and to determine the nature of the hypanthium