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Although there are many benefits associated with the use of coal fly ash in portland cement concrete, a common issue is the adsorption of air-entraining admixtures by residual carbon, which adversely affects the process of air entrainment. Currently, loss on ignition (LOI) is employed to estimate the total amount of carbon present. The LOI test does not measure the adsorption properties of the carbon, which is the important characteristic. The carbon present in fly ash may or may not be activated and the degree of activation can vary. Therefore, two ashes with the same LOI can have very different adsorption capacities. This paper presents a comparison of methods that have been developed to measure the adsorption capacity of a coal fly ash. These include the iodine number, direct adsorption isotherm, and a fluorescence-based method (FBM). The results of these methods are compared and the relative merits of each methodology are discussed. Keywords: adsorption; air-entraining admixture; air entrainment; fly ash.

Fly ash is used as partial replacement of cement in concrete. The residual carbon in fly ash adsorbs some of the organic concrete admixtures, altering the concrete properties. The use of fly ash in concrete is limited by the lack of an adequate fly ash adsorption capacity quantification tools. This paper presents the fly ash iodine number test for the direct measurement of the adsorption capacity of coal fly ash. This test can be used to determine suitability of fly ash for concrete. The developed test was evaluated by comparing the results obtained with the loss on ignition and foam index test results for the same fly ash samples. Results show that the fly ash iodine number test can replace current qualitative indicators of adsorption capacity and can be directly used for the characterization and specification of fly ash for the use in concrete.

Electrically conductive resins can be made by adding electrically conductive fillers to typically insulating polymers. Resins with an electrical resistivity of approximately 100 ohm‐cm or less can be used for electromagnetic and radio frequency interference shielding applications. This research focused on performing compounding runs followed by injection molding and shielding effectiveness testing of carbon filled nylon 6,6 based resins. The three carbon fillers investigated included an electrically conductive carbon black, synthetic graphite particles, and a surface‐treated polyacrylonitrile (PAN)‐based carbon fiber. Conductive resins were produced and tested that contained varying amounts of these single carbon fillers. In addition, combinations of fillers were investigated by conducting a full 23 factorial design and a complete replicate. The objective of this paper was to determine the effects and interactions of each filler on the shielding effectiveness properties of the conductive resins. Carbon fiber caused the largest increase in shielding effectiveness. Also, all the single fillers and combinations of fillers were statistically significant at the 95% confidence level, except the composite containing carbon black and synthetic graphite particles tested at 800 MHz. Polym. Compos. 25:407–416, 2004. © 2004 Society of Plastics Engineers.

This guide provides background and examples for the use of practical aggregate grading tools to improve aggregate performance in concrete and allow the paste content of a concrete mixture to be reduced while achieving satisfactory workability and physical properties. The aggregate grading of a concrete mixture impacts the workability, durability, strength, and sustainability of concrete. These grading tools can also be used to proportion concrete mixtures as well as troubleshoot issues associated with mixtures from high to low workability. This guide docs not make recommendations, but it does describe and give examples on how to use these tools.

This reference specification provides requirements for curing concrete that the architect/engineer can apply to any construction project by citing it in the project specification. Checklists are provided to assist the architect/ engineer in supplementing the provisions of this reference specification as needed by designating or specifying customized project requirements. This specification provides requirements for various methods for the external curing of concrete. These methods are not necessarily equal in effectiveness, cost, effect on the project schedule, or impact on other aspects of the project. Provisions governing initial, final, and termination of curing are included. This specification addresses external curing methods applied after the placement of cast-in-place concrete. While internal curing (use of saturated lightweight aggregate or other materials to provide supplemental water) and accelerated curing (heat curing) shall also use external curing methods, not all aspects of internal and accelerated curing are included.

This reference specification provides requirements for curing concrete that the architect/engineer can apply to any constraction project by citing it in the project specification. Checklists are provided to assist the architect/ engineer in supplementing the provisions of this reference specification as needed by designating or specifying customized project requirements. This specification provides requirements for various methods for the external curing of concrete. These methods are not necessarily equal in effectiveness, cost, effect on project schedule, or impact on other aspects of the project. Provisions governing initial, final, and termination of curing are included. This specification addresses external curing methods applied after placement of cast-in-place concrete. While internal curing (use of satmated lightweight aggregate or other materials to provide supplemental water) and accelerated curing (heat curing) shall also use external curing methods, not all aspects of internal and accelerated curing are included.

Background Neonatal Opioid Withdrawal Syndrome (NOWS) is a significant public health issue and while millions of neonates are affected each year, an optimal pharmacologic weaning protocol has yet to be demonstrated. In this study, we compare hospital length of stay (LOS) and length of treatment (LOT) for treatment of neonatal opioid withdrawal (NOWS) with morphine versus methadone. Methods This was a single-site, open-label, randomized controlled pilot study conducted from October 2016-September 2018. Infants were eligible if their primary in-utero drug exposure was heroin, oral opioids, or methadone and they were born at greater than or equal to 34 weeks gestation. Infants were excluded for serious medical comorbidities and primary in-utero exposure to buprenorphine. Results Sixty-one infants were enrolled; 30 were randomized to methadone treatment, and 31 to morphine treatment. Overall 46% of infants required treatment for NOWS. LOS and LOT for infants treated with morphine was 17.9 days and 14.7 days respectively, compared to 16.1 days and 12.8 days for babies treated with methadone ( p  = 0.5, p  = 0.54). Infants treated with morphine received lower total morphine equivalents than those treated with methadone (9.7 vs. 33, p  < 0.01). Three treated infants in the methadone group required transfer to the Neonatal Intensive Care Unit, versus no infants in the morphine group. Conclusions Infants treated with morphine versus methadone had no significant differences in LOS or LOT in this pilot study. Infants treated with methadone received up to 3 times the opioid based on morphine equivalents as infants treated with morphine and had more transfers to the NICU for over sedation. Clinical trial registration Morphine Versus Methadone for Opiate Exposed Infants With Neonatal Abstinence Syndrome NCT02851303 , initiated 01/08/2016.

Background. Polio eradication efforts have been hampered by low responses to trivalent oral poliovirus vaccine (tOPV) in some developing countries. Since stomach acidity may neutralize vaccine viruses, we assessed whether administration of a buffer solution could improve the immunogenicity of tOPV. Methods. Healthy infants 4-6 weeks old in Sylhet, Bangladesh, were randomized to receive tOPV with or without a sodium bicarbonate and sodium citrate buffer at age 6, 10, and 14 weeks. Levels of serum neutralizing antibodies for poliovirus types 1, 2, and 3 were measured before and after vaccination, at 6 and 18 weeks of age, respectively. Findings. Serologie response rates following 3 doses of tOPV for buffer recipients and control infants were 95% and 88% (P = .065), respectively, for type 1 poliovirus; 95% and 97% (P = .543), respectively, for type 2 poliovirus; and 90% and 89% (P = .79), respectively, for type 3 poliovirus. Conclusions. Administration of a buffer solution prior to vaccination was not associated with statistically significant increases in the immune response to tOPV; however, a marginal 7% increase (P = .065) in serologie response to poliovirus type 1 was observed. Clinical Triah Registration. NCT01579825.

Hereditary nonpolyposis colorectal cancer syndrome (HNPCC) is an autosomal dominant condition accounting for 2-5% of all colorectal carcinomas as well as a small subset of endometrial, upper urinary tract and other gastrointestinal cancers. An assay to detect the underlying defect in HNPCC, inactivation of a DNA mismatch repair enzyme, would be useful in identifying HNPCC probands. Monoclonal antibodies against hMLH1 and hMSH2, two DNA mismatch repair proteins which account for most HNPCC cancers, are commercially available. This study sought to investigate the potential utility of these antibodies in determining the expression status of these proteins in paraffin-embedded formalin-fixed tissue and to identify key technical protocol components associated with successful staining. A set of 20 colorectal carcinoma cases of known hMLH1 and hMSH2 mutation and expression status underwent immunoperoxidase staining at multiple institutions, each of which used their own technical protocol. Staining for hMSH2 was successful in most laboratories while staining for hMLH1 proved problematic in multiple labs. However, a significant minority of laboratories demonstrated excellent results including high discriminatory power with both monoclonal antibodies. These laboratories appropriately identified hMLH1 or hMSH2 inactivation with high sensitivity and specificity. The key protocol point associated with successful staining was an antigen retrieval step involving heat treatment and either EDTA or citrate buffer. This study demonstrates the potential utility of immunohistochemistry in detecting HNPCC probands and identifies key technical components for successful staining.