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When a building requires a long span, especially on the ground floor of a multistory building, the long span often determines the structural system used early in the design process without any other consideration. Commercial and residential buildings are responsible for roughly 40% of all carbon emissions and energy use, more than any other sector in the USA. Moreover, this excludes the significant energy and emissions required to extract, process, transport and assemble building components. Globally, the production of cement alone accounts for 4% of carbon dioxide emissions. Consequently, reducing the environmental impact of building construction and operations is critical to address interrelated issues such as global climate change. The role of structural systems in the overall performance of a building has been largely neglected. Very little consideration is given to other ways the structure could contribute to improving sustainable outcomes. This is in spite of the fact that the structure of a typical office building contributes roughly one-quarter of the total embodied energy and is, at the very least, the armature for all other building systems. Existing research into the embodied energy of structural systems focuses on hypothetical office buildings with uniform structural layouts, a range of comparable, existing office buildings or housing without comparing or accounting for the long spans. Like all other aspects of a building, the structural system needs to be understood in terms of wide range of sustainability issues: embodied energy, operational energy, longevity and reuse. If structural systems could be left exposed without additional finishes as well as be configured to provide a higher level of thermal comfort, more daylight and acoustic isolation, this could significantly reduce the operational energy and the initial materials required for new construction. These multi-performance structural systems, in contrast to high-performance structural materials that aim to only improve structural properties, offer considerable and largely untapped opportunities to improve new and existing buildings while potentially lowering construction costs. Using a five-story, 2,500 square-meter (27,000 square-foot) classroom building with 24.4 meters by 30.5 meters (80 feet by 100 feet) auditorium on the ground floor as a case study currently in design at Oregon State University, the multi-performance criteria for three long span systems, including steel, concrete and wood, are compared. These criteria include embodied energy and carbon, structural and spatial properties, acoustical properties, fire protection and thermal properties. This paper argues that the most efficient structural solution may not be the best in terms of overall sustainability outcomes, and the selection of a structural system should be based on multi-performance criteria.

The boron isotopic composition (δ11B) of marine carbonates (e.g. corals) has been established as a reliable proxy for paleo-pH, with the strong correlation between δ11B of marine calcifiers and seawater pH being now well documented. However, further investigations are needed in order to better quantify other environmental parameters potentially impacting boron isotopic composition and boron concentration into coral aragonite. To achieve this goal the tropical scleractinian coral Acropora sp. was cultured under 3 different temperature (22, 25 and 28 °C) and two light conditions (200 and 400 μmol photon m−2 s−1). The δ11B indicates an internal increase in pH from ambient seawater under both light conditions. Changes in light intensities from 200 to 400 μmol photon m−2 s−1 could bias pH reconstructions by about 0.05 units. For both light conditions, a significant impact of temperature on δ11B can be observed between 22 and 25 °C corresponding to enhancements of about 0.02 pH-units, while no further δ11B increase can be observed between 25 and 28 °C. This non-linear temperature effect complicates the determination of a correcting factor. B/Ca ratios decrease with increasing light, confirming the decrease in pH at the site of calcification under enhanced light intensities. When all the other parameters are maintained constant, boron concentrations in Acropora sp. increase with increasing temperature and increasing carbonate ions concentrations. These observations contradict previous studies where B/Ca in corals was found to vary inversely with temperature suggesting that the controlling factors driving boron concentrations have not yet been adequately identified and might be influenced by other seawater variables and species specific responses.

Here we show the use of the 210Pb-226Ra excess method to determine the growth rate of corals from one of the world's largest known cold-water coral reef, the Røst Reef off Norway. Two large branching framework-forming cold-water coral specimens, one Lophelia pertusa and one Madrepora oculata were collected alive at 350 m water depth from the Røst Reef at ~67° N and ~9° E. Pb and Ra isotopes were measured along the major growth axis of both specimens using low level alpha and gamma spectrometry and the corals trace element compositions were studied using ICP-QMS. Due to the different chemical behaviors of Pb and Ra in the marine environment, 210Pb and 226Ra were not incorporated the same way into the aragonite skeleton of those two cold-water corals. Thus to assess of the growth rates of both specimens we have here taken in consideration the exponential decrease of initially incorporated 210Pb as well as the ingrowth of 210Pb from the decay of 226Ra. Moreover a~post-depositional 210Pb incorporation is found in relation to the Mn-Fe coatings that could not be entirely removed from the oldest parts of the skeletons. The 226Ra activities in both corals were fairly constant, then assuming constant uptake of 210Pb through time the 210Pb-226Ra chronology can be applied to calculate linear growth rate. The 45.5 cm long branch of M. oculata reveals an age of 31 yr and a~linear growth rate of 14.4 ± 1.1 mm yr−1, i.e. 2.6 polyps per year. However, a correction regarding a remaining post-depositional Mn-Fe oxide coating is needed for the base of the specimen. The corrected age tend to confirm the radiocarbon derived basal age of 40 yr (using 14C bomb peak) with a mean growth rate of 2 polyps yr−1. This rate is similar to the one obtained in Aquaria experiments under optimal growth conditions. For the 80 cm-long specimen of L. pertusa a remaining contamination of metal-oxides is observed for the middle and basal part of the coral skeleton, inhibiting similar accurate age and growth rate estimates. However, the youngest branch was free of Mn enrichment and this 15 cm section reveals a growth rate of 8 mm yr−1 (~1 polyp every two to three years). However, the 210Pb growth rate estimate is within the lowermost ranges of previous growth rate estimates and may thus reflect that the coral was not developing at optimal growth conditions. Overall, 210Pb-226Ra dating can be successfully applied to determine the age and growth rate of framework-forming cold-water corals, however, removal of post-depositional Mn-Fe oxide deposits is a prerequisite. If successful, large branching M. oculata and L. pertusa coral skeletons provide unique oceanographic archive for studies of intermediate water environmentals with an up to annual time resolution and spanning over many decades.

We surveyed healthcare workers (HCWs) about influenza vaccination and routine childhood vaccinations. We found that most HCWs' children received vaccinations, despite concerns regarding safety and efficacy. HCWs who received influenza vaccine were more likely to immunize their children against influenza, although a substantial proportion of HCWs' children did not receive influenza vaccination.

To determine the attitudes, beliefs, and knowledge of children's hospital health care workers toward mandatory influenza vaccination.Self-administered, Web-based questionnaire.A large, tertiary children's hospital.A random sample of 585 health care workers, including physicians, nurses, and all other hospital employees. Outcome Measure Attitudes of health care workers toward mandatory policies for annual influenza vaccination of health care workers as related to their opinions on safety, effectiveness, and knowledge about influenza and influenza vaccination.Many employees (70%) thought influenza vaccination should be mandatory for health care workers who did not have a medical contraindication. Nearly everyone, 363 of 391 (94%), who favored mandatory immunization had been immunized themselves. Of those who opposed mandatory immunization, 45 of 81 (55.6%) had been immunized (P.001). Individuals who supported mandatory policies were more likely to believe that the vaccine is safe for both children and adults. There was no significant difference between the percentages of promandate and antimandate employees who believed influenza was dangerous for the patients where they work (66.5% and 62%, respectively, P = .07). Only 29% of antimandate employees believed they were at high risk of contracting influenza, compared with 51% of promandate employees (P.001).Approval of mandatory influenza vaccine policies was high; however, attitudes about the dangers of influenza for patients were not associated with acceptance of mandatory vaccination policies for health care workers. Educational efforts targeting health care workers' fears and misconceptions about influenza vaccines might help to decrease the reservoir of unimmunized health care workers.