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Sujatha Seetharaman,1 Cathryn L Samples,2 Maria Trent3 1Division of Adolescent Medicine, Stanford University Medical Center, Palo Alto, CA, 2Division of Adolescent Medicine, Boston Children’s Hospital, Harvard Medical School, Boston, MA, 3Division of General Pediatrics and Adolescent Medicine, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins School of Medicine, Baltimore, MD, USA Purpose: The purpose of this study was to determine whether there is adherence to the October 2011 American Academy of Pediatrics (AAP) recommendations for HIV screening in a large urban adolescent program with availability of a publicly funded program providing free, confidential, sexually transmitted infection (STI) and HIV counseling and testing (then rapid or third generation HIV testing), nested in the same adolescent clinic.Methods: We conducted a retrospective chart review of HIV screening trends among 13- to 24-year-old patients tested for HIV during periods of January 2010 to June 2011 (18 months pre-AAP recommendations period) and July 2011 to December 2012 (18-month period, which included 15 months after the AAP recommendations).Results: During the period of January 2010 to June 2011, there were 22 tests/1,000 medical visits (N = 824 of 37,520 medical visits), and during the period of July 2011 to December 2012, there were 27 tests/1,000 medical visits (N = 1,068 of 38,763 medical visits) (p < 0.0001, odds ratio [OR] 1.26). The number of 13- to 18-year-old patients screened in the pre-AAP period was 150, compared to 297 in the second 18-month period (X2 = 43.3, df = 1, p < 0.0001). A summative risk profile score of 0–9 was created in the form of a continuous variable, with a risk score of 0 for those with no risk factor identified and 1 point for each risk behavior identified. The proportion of HIV test clients with zero-specified risk (a risk score of “0”) increased from 2010 to 2012.Conclusion: Release of the 2011 AAP HIV testing guidelines was associated with a modest increase in HIV screening and a shift toward testing younger people and away from risk-based screening. Keywords: adolescents, HIV screening, 2011 AAP HIV recommendations, risk-based HIV screening, HIV risk factors

Sujatha Seetharaman, Sophia Yen, Seth D Ammerman Division of Adolescent Medicine, Stanford University Medical Center, Palo Alto, CA, USA Abstract: Globally, unintended adolescent pregnancies pose a significant burden. One of the most important tools that can help prevent unintended pregnancy is the timely use of emergency contraception (EC), which in turn will decrease the need for abortions and complications related to adolescent pregnancies. Indications for the use of EC include unprotected sexual intercourse, contraceptive failure, or sexual assault. Use of EC is recommended within 120 hours, though is most effective if used as soon as possible after unprotected sex. To use EC, adolescents need to be equipped with knowledge about the various EC methods, and how and where EC can be accessed. Great variability in the knowledge and use of EC around the world exists, which is a major barrier to its use. The aims of this paper were to 1) provide a brief overview of EC, 2) discuss key social determinants affecting knowledge and use of EC, and 3) explore best practices for overcoming the barriers of lack of knowledge, use, and access of EC. Keywords: emergency contraception, adolescents, unintended pregnancy, unprotected sexual intercourse

The advantages of using CO2 for the decarburization of high alloy steels have been recognized from environmental and economic view points. The present paper presents the heat and materials balances in the decarburization process with the introduction of CO2 as a diluting gas in Electric Arc Furnace (EAF) process for steel production. The aim is to optimize the amount of CO2 and the materials requirements, which includes the addition of scrap, hot metal and coolant. These estimations are also important to control the bath temperature, thereby prolong the lifetime of the refractory lining of the furnace. The present calculations enable an optimization of the CO2:O2 ratio and materials input in the decarburization of carbon steel melts. Another important extension of the work is the possibility to enhance the addition of hot metal during steel making process. The present results show that addition of up to 20% hot metal is likely to the energy loss due to the introduction of 50% CO2 for a 110 tons EAF resulting in the saving of electric energy.

In this work, we successfully applied the Fray-Farthing-Chen Cambridge electro-reduction process on the preparation of chromium from chromium oxide, and for the first time, the synthesis of ferrochromium alloy from chromium oxide and iron oxide mixture and the chromite ore in molten calcium chloride. The present work systematically investigated the influences of sintered temperature of the solid precursor, electrochemical potential, electrolysis temperature and time on the products by using a set of advanced characterization techniques, including XRD and SEM/EDS analyses. In particular, our results show that this process is energy-friendly and technically-feasible for the direct extraction of ferrochromium alloy from chromite ore. Our findings thus provide useful insights for designing a novel green process to produce ferrochromium alloy from low-grade chromite ore or stainless steel slag.

Chromium is a high value metal and the retention of the same during the refining of high carbon ferrochrome as well as high alloy steel has significant economic and environmental impacts. The loss of chromium during the decarburization is generally minimized using argon-oxygen mixtures thereby reducing the oxygen partial pressure (PO2) of the oxidant gas. In the current study, experiments were carried out in an induction furnace and CO2 was introduced with the view to partly reduce PO2 and partly as an oxidizer. During these experiments, the decarburization of molten Cr-alloy was conducted using pure O2, pure CO2 or O2+CO2 mixtures. The results demonstrated that the Cr loss can be minimized under CO2 introduction. The kinetic analysis showed that the mass transfer is effective due to the production of 2CO gas molecules from one CO2 molecule during the reaction which will improve the stirring of the bath. Besides, CO2 reacts with carbon in melt is an endothermic reaction, introduction of CO2 could be a cooler during the refining process, hence the temperature could be controlled by controlling the diluting gas amount, in this case, the over heat of bath refractory could be prevented and the lifetime of refractory could be extended.

Sustainable development of steelmaking requires solving a number of environmental problems. Economically feasible and environmentally friendly recycling of slag wastes is of special concern. Research of the team representing National Metallurgical Academy of Ukraine, Royal Institute of Technology, Carnegie Mellon University and URS Corp revealed a possibility of the controlled phase transformations in the liquid silicate melts followed by formation of the magnetically susceptible compounds. This approach enables selective recovery of metal values from slag. In this paper, the results obtained and further research directions are discussed. A possibility to exploit physical properties of the transition metals, typical for the metallurgical slags (such as Fe, Mn, V and others), and corresponding specific properties of their compounds, such as non-stoichiometry, mixed valency, pseudomorphosis, thermodynamic stability etc, in production of value-added materials from slag wastes is discussed. The results of the studies of thermodynamics and kinetics of oxidation in slags followed by phase transformation with binary, ternary and complex oxides under various physicochemical conditions are discussed in the view of their application for production of the materials with predefined physical properties. Peculiarities of precipitation in slags with various basicities are analysed and demonstrate capacity of the proposed approach in the production of the material with a given structure and size - for example, nano-sized crystals with structure of spinel. The approaches towards industrial realization of the developed method are also discussed.

Direct chromium alloying by chromite ore in EAF operation is a promising process in stainless steel production, which has the advantage of resource-saving, energy-saving, and environment-friendly. In the present investigation, iron, carbon, and chromite ore mixture (Fe+C+FeCr2O4) were chosen as the precursor for direct chromium alloying. Thermogravimetric Analysis (TGA) experiments were carried out to investigate the effect of iron content on the reduction kinetics, and the results show that the presence of metallic iron in the precursor will increase the reduction rate of chromite. Up-scaling experiments (100 g and 500 g scale) have been carried out in the induction furnace to further test the effectiveness of using industrial chromite ore for direct chromium alloying. The induction furnace tests confirmed the necessity of adjusting composition of the slags to ensure high yield of chromium in the final products; and chromium yield can reach 90%.

The importance of experimentation as an ingredient to CALPHAD assessments is brought out in the present paper and is illustrated in the case of a number of metallic and oxidic systems. Two types of experimental techniques have been used in the present laboratory for thermodynamic studies, and the details are presented. The results obtained together with the assessed phase diagram in the case of a few selected systems are presented. It was shown that careful experimentation has brought new features in the case of carbide systems involving Mn, and a new 4-phase equilibrium in the case of Ni-W-O system. New data with regard to the thermodynamic activities of FeO-containing slag systems and sulphide capacities of multicomponent slags, obtained by gas equilibration method, are also presented. A thermodynamic software, THERMOSLAG© based on the experimental data has been found to be extremely useful by the steel industries is also discussed.

E‐glass/epoxy prepregs are undisputedly a great advancement in processing and fabrication technology. They offer immense advantages over conventional composite manufacturing processes in terms of waste reduction and efficient manufacturing times. These prepregs are used in several industries including but not limited to automobile, construction, defense and aerospace. Their versatility and wide applicability however is shadowed by intricate storage and handling requirements. Prepregs usually need to be stored at below freezing temperatures and hence lose their chemical integrity during transportation if not handled properly leading to a lot of wastage and scrap generation. Therefore, it is essential to develop a rigorous regime in order to determine the shelf‐life and usability of these prepregs. Hereby, we report an extensive experimental design for assessing shelf‐life of commercially available prepregs using techniques like DSC and IR and corelating the findings with mechanical data. The degree of pre‐cure increased to 30% as a result of exposure to moisture over prolonged time and a substantial decrease in mechanical strength was observed. The shelf‐life was found to be about 7 weeks and a strong agreement between analytical and mechanical data was observed. Highlights: Analysis of prepreg aging under ambient and accelerated storage conditions.Measurement of prepreg auto‐cure advancement using IR, Raman and DSC techniques.Comprehensive assessment of effect of moisture and temperature on prepreg integrity and tackiness.Co‐relation of spectroscopic and calorimetric data with mechanical properties of laminates prepared from aged prepregsEstimation of prepreg shelf‐life on exposure to room temperature simulating conditions. [ABSTRACT FROM AUTHOR]