Learning from the U.S. National Assessment of Climate Change Impacts

The U.S. National Assessment of the Potential Consequences of Climate Variability and Change was a federally coordinated nationwide effort that involved thousands of experts and stakeholders. To draw lessons from this effort, the 10 authors of this paper, half of whom were not involved in the Assessment, developed and administered an extensive survey, prepared a series of working papers, and conducted an invitational workshop in Washington, DC, on April 29, 2004. Considering all these sources, the authors conclude that the Assessment was largely successful in implementing its basic design of distributed stakeholder involvement and in achieving its basic objectives. Future assessments could be significantly improved if greater attention were devoted to developing a collective understanding of objectives, preparing guidance materials and providing training for assessment participants, developing a budgeting mechanism which would allow greater freedom in allocating resources across various assessment activities, and creating an environment in which assessments were part of an ongoing process.     

Improving the Yield of Sonochemical Precipitated Aragonite Synthesis by Scaling up Intensified Conditions

Precipitated aragonite can be synthesized at relatively low temperatures by combining the application of low-frequency sonication with the use of magnesium chloride additive, as demonstrated by our prior study. In the present study, new process conditions were found that promote aragonite formation while accelerating and increasing the reaction yield. It was found that Mg-to-Ca molar ratio of 3:1, together with higher slurry concentration (74 g/L Ca(OH)₂) and higher power-to-volume ratio (800 W/L gross, achieved by reducing slurry volume), promoted the aragonite formation while working at a higher CO₂ flow rate (2.0 NL/min), and consequently higher precipitated calcium carbonate production rate (1 g/(L · min) CaCO₃). The yield was thus improved while conserving the desired product properties as follows: high polymorph purity (95.7 wt%), small and narrow particle size distribution (D[3,2] = 0.74 µm), and unique shape (hubbard squash-like).     

Lipophilization of dihydrocaffeic acid affects its antioxidative properties in fish‐oil‐enriched emulsions

The aim of the present study was to evaluate the antioxidative effect of lipophilized dihydrocaffeic acid, i.e., octyl dihydrocaffeate and oleyl dihydrocaffeate. Furthermore, the relationship between the measured efficacy of the antioxidants in emulsions, their partitioning into different phases of an emulsion system and their in vitro antioxidant properties was also evaluated. Lipid oxidation in the emulsions was affected by the antioxidants applied. Thus, despite a reduced antioxidant activity of lipophilized dihydrocaffeic acid in the antioxidant assays, lipophilized dihydrocaffeic acid was more efficient than caffeic and dihydrocaffeic acids. Octyl dihydrocaffeate had a significantly higher antioxidative effect than oleyl dihydrocaffeate in emulsions. The results partly supported the polar paradox hypothesis, since lipophilized compounds resulted in increased oxidative stability. However, the decreased antioxidative efficacy with increasing alkyl chain length esterified to dihydrocaffeic acid supported a newly suggested cut‐off effect hypothesis. This hypothesis suggests that when a certain level of hydrophobicity is obtained for lipophilized phenolic acids, the ester forms micelles in the aqueous phase rather than being located at the interface or oil phase. This phenomenon is suggested to explain the reduced antioxidant activity of oleyl dihydrocaffeate compared with octyl dihydrocaffeate. Practical application: The finding that lipophilization of phenolic compounds increase their efficacy opens up new possibilities for producing new and more efficient antioxidants for food systems. However, the results also show that optimization of the chain length for each type of phenolic compound may be necessary. Since these compounds may have a much higher efficacy against lipid oxidation a lower amount of antioxidant will be necessary to obtain the same effect. This would decrease the costs. In addition, the use of synthetic antioxidants, that might have toxic effect in vivo, can be avoided. The raw materials used for the lipophilized compounds are natural compounds, however the fate of the lipophilized compounds in vivo should eventually be evaluated.     

促进步行与骑车出行:评估文献证据献计规划人员

如何鼓励人们更多地以步行或者骑车作为出行方式?本文分析了超过300项精心设计的实证研究的结果,以指导如何用一些具体的策略来影响人们选择步行或骑车作为出行的方式.这些策略包括:社区的设计、基础设施的可用性、基础设施的质量、推广方案、定价以及组合策略.具有较高的步行和骑车出行水平的城市环境,通常是多种促进因素共同作用的反映.     

应用显微技术观察未涂布纸中墨滴渗透图像的研究

摘译 墨滴在纸页结构中的渗吸是一个非常复杂的过程.纸页中的孔隙以纳米级尺寸存在于纤维(纤维之间或几微米的大孔径)及其细胞壁中.墨滴的渗吸过程包括纤维间孔隙的毛细管作用、在纤维内部和细胞壁微孔中的渗透,以及沿纤维的表面扩散.喷墨墨滴大小只达到皮升级,因此纤维的芯吸效应和墨水在纤维表面的扩散起主要作用.     

Protein-binding approaches for improving bioaccessibility and bioavailability of anthocyanins

Color is an important characteristic of food. Over the last 15 years, more attention has been paid to natural colorants because of the rising demand for clean-label food products. Anthocyanins, which are a group of phytochemicals responsible for the purple, blue or red hues of many plants, offer a market advantage. In addition, anthocyanin-rich foods are associated with protection against cardiovascular disease, thrombosis, diabetes, cancer, microbial-based disorders, neurological disorders, and vision ailments. However, the real health value of anthocyanins, whether as a natural colorant or a functional ingredient, is dependent on the ultimate bioaccessibility and bioavailability in the human body. Many animal and human clinical studies revealed that, after intake of anthocyanin-rich foods or anthocyanin extracts, only trace amounts (< 1% of ingested content) of anthocyanins or their predicted metabolites were detected in plasma after a standard blood draw, which was indicative of low bioavailability of anthocyanins. Protein binding to anthocyanins is a strategy that has recently been reported to enhance the ultimate bioactivity, bioaccessibility, and bioavailability of anthocyanins as compared to anthocyanins delivered without a protein carrier. Therefore, in this review, we address anthocyanin properties in food processing and digestion, anthocyanin-protein complexes used in food matrices, and changes in the bioaccessibility and bioavailability of anthocyanins when bound into anthocyanin-protein complexes in foods. Finally, we summarize the challenges and prospects of this delivery system for anthocyanin pigments.     

Comparison of the Effects of Biodiesel and Mineral Diesel Fuel Dilution on Aged Engine Oil Properties

Dilution of engine oil occurs when fuel is injected late in the combustion cycle to regenerate the diesel particulate filter used for trapping particulate emissions. Fuel dilution reduces oil viscosity and the concentration of engine oil additives, potentially compromising lubricant performance. Biodiesel usage may compound these issues due to its oxidative instability, and its higher boiling point compared to mineral diesel potentially causes it to concentrate more in the oil sump.

In this work, different amounts of mineral diesel and biodiesel (soy methyl ester, SME) were combined with 15W-40 CJ-4 diesel engine oil in laboratory oil aging experiments. Fuel was added and oil samples were withdrawn at periodic intervals. The oils were analyzed using typical oil analysis procedures to determine their condition, and wear evaluations under boundary lubricating conditions were determined using a high-frequency reciprocating rig (HFRR). Results showed that fuel dilution accelerated engine oil degradation, with biodiesel having a larger effect. However, friction remained unchanged with dilution, and wear actually decreased for fuel-diluted oils after 48 h of aging compared to aging without fuel dilution. Examination of the tribofilms by ultraviolet (UV) and visible Raman spectroscopy as well as Auger electron spectroscopy showed that additional carbon-containing components were present on tribofilms formed from fuel-diluted oils. These fuel-derived components may be responsible for the decreased wear observed.     

Influence of pilot scale in pack pasteurization and sterilization treatments on nutritional and textural characteristics of carrot pieces

The current work presents a pilot scale study in which the effect of in pack thermal preservation processes in a retort system on particular carrot quality aspects, more specifically nutritional and textural characteristics, was investigated. Pasteurization as well as sterilization processes with different intensities were included. The carrot hardness, analyzed by a compression test, and the β-carotene bio-accessibility, analyzed by an in vitro digestion method, were the main quality markers. As a main conclusion, it can be stated that the results of this pilot scale study are a good validation of results obtained during previous laboratory scale experiments on carrot nutritional and textural characteristics. The processes applied in this study only resulted in limited conversion of all-trans-β-carotene to its cis-isomers. Furthermore, it was shown that intense thermal processing is required to observe a significant increase in the β-carotene bio-accessibility. However, this was accompanied with a clear degradation of the hardness. When thermal processing was preceded by low temperature blanching, a technique to improve texture retention of thermally processed plant-based foods, a lower β-carotene bio-accessibility was observed. Both observations clearly illustrated the inverse correlation between textural and nutritional characteristics of (processed) carrots. Statistical analyses confirmed the trends observed. For process design, the choice of the process intensity was identified to be crucial: the required product safety needs to be achieved, while still reaching an acceptable structural and nutritional quality. Exploring strategies to enhance the β-carotene bio-accessibility while ensuring an acceptable carrot texture can therefore be useful.     

Performance metrics and auditing framework using application kernels for high‐performance computer systems

This paper describes XSEDE Metrics on Demand, a comprehensive auditing framework for use by high‐performance computing centers, which provides metrics regarding resource utilization, resource performance, and impact on scholarship and research. This role‐based framework is designed to meet the following objectives: (1) provide the user community with a tool to manage their allocations and optimize their resource utilization; (2) provide operational staff with the ability to monitor and tune resource performance; (3) provide management with a tool to monitor utilization, user base, and performance of resources; and (4) provide metrics to help measure scientific impact. Although initially focused on the XSEDE program, XSEDE Metrics on Demand can be adapted to any high‐performance computing environment. The framework includes a computationally lightweight application kernel auditing system that utilizes performance kernels to measure overall system performance. This allows continuous resource auditing to measure all aspects of system performance including filesystem performance, processor and memory performance, and network latency and bandwidth. Metrics that focus on scientific impact, such as publications, citations and external funding, will be included to help quantify the important role high‐performance computing centers play in advancing research and scholarship. Copyright © 2012 John Wiley & Sons, Ltd.