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Due to their chemical and physical properties, rare earth elements (REEs) are essential in modern applications such as energy conversion or IT technology. The increasing demand for these elements leads to strong incentives for REE recovery and induces the exploration of new, alternative sources for REEs. Accessing REEs from clay minerals, in our case kaolinite, by an elution process is a promising method. The present study investigates the potential application of REE recovery through elution with different mineral acids (HNO3, H2SO4, and HCl) in a microwave process. The material used in this study—residues from an industrial kaolin production process—contained 2.47 g/kg REEs which is a significant amount for REE recovery. The ability of various mineral acids to solubilize metals was studied to assess the REE content of this residual resource. Around 1.87 g/kg of REEs was eluted from industrial kaolinite residues in hydrochloric acid, 1.71 g/kg in sulfuric acid, and 1.13 g/kg in nitric acid. [ABSTRACT FROM AUTHOR]

Elevated carbon dioxide (eCO2) and rising temperatures will have far‐reaching effects on global plant‐insect interactions, yet their implications for future biological control programs are not fully understood. Studies have shown that elevated CO2 will affect insect feeding guilds differently and these responses can be predicted with some confidence. Water hyacinth, Pontederia crassipes Mart. (Pontederiaceae), is a native and representative species of the Del Plata wetlands (Argentina) that invades outside of its native environment. It is considered one of the world's worst aquatic weeds and a target for biological control. In this study, water hyacinth plants were grown under two CO2 concentrations – current (400 p.p.m.) or elevated (800 p.p.m.) –, with and without two biocontrol agents representing different feeding guilds, the leaf‐chewing Cornops aquaticum Brüner (Orthoptera: Acrididae) and the phloem‐feeding Megamelus scutellaris Berg (Hemiptera: Delphacidae). Under eCO2 concentration, photosynthetic rate, total dry weight, and relative growth rate of P. crassipes acclimated to eCO2 conditions and plants showed very little CO2 fertilization response in eutrophic water. Insect herbivory varied depending on feeding guilds at eCO2; however, P. crassipes growth responses increased when exposed to insect herbivory. Chewing herbivory by C. aquaticum was consistent across CO2 conditions, whereas the feeding by M. scutellaris increased substantially at eCO2. These results indicate that successful biological control of P. crassipes under conditions of elevated CO2 might rely on phloem‐feeding insects, with chewers playing a lesser role. [ABSTRACT FROM AUTHOR]

Systems engineering activities in the concept and development phases have evolved continuously for decades. The deployment of digital thread, digital engineering, MBSE approaches, and modeling and simulation techniques have driven part of this evolution. Despite this trend, requirements are still largely textual and expressed in natural language, and requirements engineering activities are still often document‐based. However, model‐based requirements‐engineering approaches have emerged in recent years and have demonstrated significant benefits, including improved requirements quality, less ambiguity, and early and efficient verification and validation. The goal of this paper is to present the current outcomes and perspectives of setting up an Integrated Digital Requirements Engineering approach as developed within our company. This approach seeks to optimize usability and maximize benefits to support end‐to‐end V&V activities while fully integrating into MBSE workflows. [ABSTRACT FROM AUTHOR]

Iron reduction and sulfate reduction often occur simultaneously in anoxic systems, and where that is the case, the molar ratio between the reactions (i.e., Fe/SO42− reduced) influences their impact on water quality and carbon storage. Previous research has shown that pH and the supply of electron donors and acceptors affect that ratio, but it is unclear how their influences compare and affect one another. This study examines impacts of pH and the supply of acetate, sulfate, and goethite on the ratio of iron to sulfate reduction in semi‐continuous sediment bioreactors. We examined which parameter had the greatest impact on that ratio and whether the parameter influences depended on the state of each other. Results show that pH had a greater influence than acetate supply on the ratio of iron to sulfate reduction, and that the impact of acetate supply on the ratio depended on pH. In acidic reactors (pH 6.0 media), the ratio of iron to sulfate reduction decreased from 3:1 to 2:1 as acetate supply increased (0–1 mM). In alkaline reactors (pH 7.5 media), iron and sulfate were reduced in equal proportions, regardless of acetate supply. Secondly, a comparison of experiments with and without sulfate shows that the extent of iron reduction was greater if sulfate reduction was occurring and that the effect was larger in alkaline reactors than acidic reactors. Thus, the influence of sulfate supply on iron reduction extent also depended on pH and suggests that iron reduction grows more dependent on sulfate reduction as pH increases. Our results compare well to trends in groundwater geochemistry and provide further evidence that pH is a major control on iron and sulfate reduction in systems with crystalline (oxyhydr)oxides. pH not only affects the ratio between the reactions but also the influences of other parameters on that ratio. [ABSTRACT FROM AUTHOR]

Methanogenesis and iron reduction play major roles in determining global fluxes of greenhouse gases. Despite their importance, environmental factors that influence their interactions are poorly known. Here, we present evidence that pH significantly influences the balance between each reaction in anoxic environments that contain ferric (oxyhydr)oxide minerals. In sediment bioreactors that contained goethite as a source of ferric iron, both iron reduction and methanogenesis occurred but the balance between them varied significantly with pH. Compared to bioreactors receiving acidic media (pH 6), electron donor oxidation was 85% lower for iron reduction and 61% higher for methanogenesis in bioreactors receiving alkaline media (pH 7.5). Thus, methanogenesis displaced iron reduction considerably at alkaline pH. Geochemistry data collected from U.S. aquifers demonstrate that a similar pattern also exists on a broad spatial scale in natural settings. In contrast, in bioreactors that were not augmented with goethite, clay minerals served as the source of ferric iron and the balance between each reaction did not vary significantly with pH. We therefore conclude that pH can regulate the relative contributions of microbial iron reduction and methanogenesis to carbon fluxes from terrestrial environments. We further propose that the availability of ferric (oxyhydr)oxide minerals influences the extent to which the balance between each reaction is sensitive to pH. The results of this study advance our understanding of environmental controls on microbial methane generation and provide a basis for using pH and the occurrence of ferric minerals to refine predictions of greenhouse gas fluxes. [ABSTRACT FROM AUTHOR]

Abstract: Relevant for engineering a wide range of technological systems, Property Model Methodology (PMM) is applied in this paper to the development process of a helicopter function in the frame of the ARP4754A/ED79A. After a short presentation of the method, the case study is presented: “to retract and to extend airborne the landing gear system”. Then, each stage of the PMM development process is illustrated by examples from the case study: (1) Modeling the top level requirements specification, (2) Validating the requirements specification by proof and simulation, (3) Modeling the architectural design, Refining the top level requirements into requirements specified to the different subsystems contributing to the function and Modeling the terminal subsystems detailed designs (4) Validating the requirements specified to the contributing subsystems by proof or simulation, (5) Verifying the design models by simulation and finally (6–8) Verifying physical implementations by test on the basis of all validation and verification scenarios accumulated throughout the development. At end, lessons learnt and industrial perspectives are summarized highlighting how PMM is a methodology adapted to the challenges facing to systems engineering by the globalization of development processes and showing how PMM can provide a powerful conceptual framework to support digital continuity within globalized Design Organizations. Modeling, simulation, proof and test generation activities are supported by the MATLAB and Simulink products. [ABSTRACT FROM AUTHOR]

Glucosylceramides (GlcCer), glucose-conjugated sphingolipids, are major components of the endomembrane system and plasma membrane in most eukaryotic cells. Yet the quantitative significance and cellular functions of GlcCer are not well characterized in plants and other multi-organ eukaryotes. To address this, we examined Arabidopsis lines that were lacking or deficient in GlcCer by insertional disruption or by RNA interference ( RNAi) suppression of the single gene for GlcCer synthase ( GCS, At2g19880), the enzyme that catalyzes GlcCer synthesis. Null mutants for GCS (designated ' gcs-1') were viable as seedlings, albeit strongly reduced in size, and failed to develop beyond the seedling stage. Heterozygous plants harboring the insertion allele exhibited reduced transmission through the male gametophyte. Undifferentiated calli generated from gcs-1 seedlings and lacking GlcCer proliferated in a manner similar to calli from wild-type plants. However, gcs-1 calli, in contrast to wild-type calli, were unable to develop organs on differentiation media. Consistent with a role for GlcCer in organ-specific cell differentiation, calli from gcs-1 mutants formed roots and leaves on media supplemented with the glucosylated sphingosine glucopsychosine, which was readily converted to GlcCer independent of GCS. Underlying these phenotypes, gcs-1 cells had altered Golgi morphology and fewer cisternae per Golgi apparatus relative to wild-type cells, indicative of protein trafficking defects. Despite seedling lethality in the null mutant, GCS RNAi suppression lines with ≤2% of wild-type GlcCer levels were viable and fertile. Collectively, these results indicate that GlcCer are essential for cell-type differentiation and organogenesis, and plant cells produce amounts of GlcCer in excess of that required for normal development. [ABSTRACT FROM AUTHOR]

The antiinflammatory effects of ethanol and aqueous extracts from Drosera rotundifolia and from Drosera madagascariensis were compared in vivo in the HET-CAM assay. Both extracts from D. rotundifolia and the ethanol extract from D. madagascariensis showed remarkable efficacy at doses of 500 µg/pellet. The inhibition of the inflammation by the extracts was stronger than that by 50 µg hydrocortisone/pellet. In contrast, there was only a very weak effect observed at a dose of 500 µg/pellet of the water extract from D. madagascariensis. The chemical analyses of the extracts showed that the effect cannot be attributed to naphthoquinones, but might be due to flavonoids. Ellagic acid obviously plays an important role in the antiangiogenic effect of the Drosera extracts. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The purpose of the research was to examine the part a creative environment plays in creating the foundation for BPR efforts. A comparison between creative environments in US and Japanese companies was used to address the research question. The creative environment of each company was examined by looking at four categories of factors--people, process, output, and environment. These categories were used to organize and systematically analyze the data. In general, the researcher found that Japanese companies tend to adopt incremental business process improvement (BPI) rather than BPR. BPI is a way of life. Emphasis is placed on the 'group' rather than the individual. Since the group is emphasized, individual innovation and creativity is not generally nurtured by management. However, some Japanese companies are beginning to see the value of individual creativity. They are starting creativity training programmes for key employees. Nevertheless, it will take some time before a paradigm of individuality is generally accepted. Since US companies want to change quickly and radically to become more competitive, many are experimenting with BPR. However, a critical success factor of BPR is teamwork and cooperation. Although US companies have historically been very individualistic, teaming and nurturing is beginning to make its way into the culture of many organizations. Successful BPR hinges on changing to an environment conducive to change. Organizations that understand the importance of a change-oriented environment will have the best chance of success. It appears that US and Japanese companies are converging on similar paradigms of work. US companies are moving from "rugged" individualism to cooperation and teamwork. Japanese companies are moving from a group consensus paradigm to one that encourages individual creativity. Although US companies have a long way to go, it might be more difficult for Japanese companies. The culture in Japan is much more homogeneous. In addition, free flow of ideas has not been a part of the Japanese culture. Whether or not companies in the US embrace teamwork and individual creativity, the basic culture of the US has always been democratic and has encouraged free speech. [ABSTRACT FROM AUTHOR]

In 1992 Barnett Bank, one of the top 25 banks in the United States, embarked on a redesign of the direct consumer lending process. The redesign involved moving from 32 to two processing centres, and has reduced processing time from three to less than one day. This case study describes Barnett Bank's approach to BPR and managing the process of redesign itself. [ABSTRACT FROM AUTHOR]

ABSTRACT "What's right with unemployment insurance" by far outweighs "What's wrong." There are, nevertheless, many flaws in the program--in philosophy, in benefits, in taxes, in administration. Most important is the need for consensus concerning primary goals. There is still no generally-accepted philosophy concerning the proper place and purpose of unemployment insurance in our economic system. Many workers currently exempt from coverage should be protected. Qualifying requirements for benefit eligibility, as well as disqualifying provisions, should be reexamined. Minimum and maximum weekly benefit amounts and potential duration provisions indicate inherent philosophies which are inconsistent and inequitable, which yield more generous benefits to unemployed secondary workers than to unemployed heads of families. Changes should relate qualifying employment and earnings, by sex, to minimum and maximum benefits and duration, in fixed proportions rather than in fixed amounts. Payroll tax bases vary considerably. Their impact among different industries is widely divergent. A supplemental flat-rate employee tax should help finance more adequate benefits. Pending agreement on primary goals, no practical solution to federal-state administrative problems can be suggested. Thereafter, however, authority and responsibility and costs should be fairly and dearly allocated between the federal government and the states. This would contribute to a much better partnership, program, and public image. [ABSTRACT FROM AUTHOR]

Chronic disorders such as haemophilia and yon Willebrand disease can rob people of a feeling of control over their lives. Added to this is often a feeling of confusion or intimidation when dealing with the healthcare system. People may begin to feel like victims of their disorders and of the healthcare system. The healthcare system defines people who are in receipt of care as patients. The word patient comes from the Latin word patiens, which means to suffer, endure, allow, permit or undergo. Even the term implies a sense of victimization. People who become partners in their care and view the receipt and delivery of healthcare as a service wherein they are the consumer and the doctor or clinician is the provider, will feel more in control and will likely have better outcomes than people who assume the more traditional role of 'patient'. [ABSTRACT FROM AUTHOR]