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  • 1
    Language: English
    In: Journal of the American Chemical Society, 16 October 2013, Vol.135(41), pp.15515-25
    Description: We report a new metallolabeled blue copper protein, Re126W122Cu(I) Pseudomonas aeruginosa azurin, which has three redox sites at well-defined distances in the protein fold: Re(I)(CO)3(4,7-dimethyl-1,10-phenanthroline) covalently bound at H126, a Cu center, and an indole side chain W122 situated between the Re and Cu sites (Re-W122(indole) = 13.1 Å, dmp-W122(indole) = 10.0 Å, Re-Cu = 25.6 Å). Near-UV excitation of the Re chromophore leads to prompt Cu(I) oxidation (〈50 ns), followed by slow back ET to regenerate Cu(I) and ground-state Re(I) with biexponential kinetics, 220 ns and 6 μs. From spectroscopic measurements of kinetics and relative ET yields at different concentrations, it is likely that the photoinduced ET reactions occur in protein dimers, (Re126W122Cu(I))2 and that the forward ET is accelerated by intermolecular electron hopping through the interfacial tryptophan: *Re//←W122←Cu(I), where // denotes a protein-protein interface. Solution mass spectrometry confirms a broad oligomer distribution with prevalent monomers and dimers, and the crystal structure of the Cu(II) form shows two Re126W122Cu(II) molecules oriented such that redox cofactors Re(dmp) and W122-indole on different protein molecules are located at the interface at much shorter intermolecular distances (Re-W122(indole) = 6.9 Å, dmp-W122(indole) = 3.5 Å, and Re-Cu = 14.0 Å) than within single protein folds. Whereas forward ET is accelerated by hopping through W122, BET is retarded by a space jump at the interface that lacks specific interactions or water molecules. These findings on interfacial electron hopping in (Re126W122Cu(I))2 shed new light on optimal redox-unit placements required for functional long-range charge separation in protein complexes.
    Keywords: Electrons ; Azurin -- Metabolism ; Rhenium -- Metabolism ; Tryptophan -- Metabolism
    ISSN: 00027863
    E-ISSN: 1520-5126
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  • 2
    Language: English
    In: Soil Biology and Biochemistry, Jan, 2015, Vol.80, p.324(17)
    Description: To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.soilbio.2014.10.018 Byline: Michael Kaiser, Markus Kleber, Asmeret Asefaw Berhe Abstract: Air-drying and wetting of air-dried soil samples with water (i.e., rewetting) are widely used sample treatments in soil analyses. It is recognized that both air-drying and rewetting of soil samples affect the characteristics of organic matter (OM), but systematic evaluations are scarce. In this review, we synthesize what is known in the scientific literature concerning the types and magnitudes of effects resulting from air-drying and rewetting with respect to i) characteristics of aggregate-associated and water-extractable OM, ii) soil microbiota, and iii) decomposition of OM. Air-drying of soil samples results in the formation of new and/or stronger OM-mineral interactions as well as increased hydrophobicity and mineral surface acidity. The formation of new and enhancement of existing OM-mineral interactions may lead to an increase in perceived aggregate stability, potentially affecting estimates of amount and persistence of OM associated with soil aggregates. Compared to field moist samples, air-dried samples had 8-41% higher relative dry mass proportions in the 2-0.25mm aggregate size fraction. Pronounced changes in the amount and composition of the water-extractable OM and soil microbiota are also detected during the course of air-drying and rewetting with the potential to affect the conclusions derived from OM decomposition experiments. Air-dried soil samples were found to have 2-10 times higher amounts of water extractable organic carbon and a decrease between 3% and 69% in the microbial biomass carbon (using the substrate-induced respiration technique) compared to field moist samples. The magnitude of air-drying and rewetting derived effects on sample characteristics appears to be site and soil type specific. Author Affiliation: (a) Life and Environmental Sciences Unit, University of California, Merced, United States (b) Department of Environmental Chemistry, University of Kassel, Germany (c) Department of Crop and Soil Science, Oregon State University, Corvallis, United States (d) Leibniz-Center for Agricultural Landscape Research (ZALF), Muncheberg, Institute of Soil Landscape Research, Germany Article History: Received 10 April 2014; Revised 16 September 2014; Accepted 19 October 2014
    Keywords: Soil Structure -- Analysis ; Microbiota (Symbiotic Organisms) -- Analysis
    ISSN: 0038-0717
    Source: Cengage Learning, Inc.
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  • 3
    Language: English
    In: Soil Biology and Biochemistry, January 2015, Vol.80, pp.324-340
    Description: Air-drying and wetting of air-dried soil samples with water (i.e., rewetting) are widely used sample treatments in soil analyses. It is recognized that both air-drying and rewetting of soil samples affect the characteristics of organic matter (OM), but systematic evaluations are scarce. In this review, we synthesize what is known in the scientific literature concerning the types and magnitudes of effects resulting from air-drying and rewetting with respect to i) characteristics of aggregate-associated and water-extractable OM, ii) soil microbiota, and iii) decomposition of OM. Air-drying of soil samples results in the formation of new and/or stronger OM-mineral interactions as well as increased hydrophobicity and mineral surface acidity. The formation of new and enhancement of existing OM-mineral interactions may lead to an increase in perceived aggregate stability, potentially affecting estimates of amount and persistence of OM associated with soil aggregates. Compared to field moist samples, air-dried samples had 8–41% higher relative dry mass proportions in the 2–0.25 mm aggregate size fraction. Pronounced changes in the amount and composition of the water-extractable OM and soil microbiota are also detected during the course of air-drying and rewetting with the potential to affect the conclusions derived from OM decomposition experiments. Air-dried soil samples were found to have 2–10 times higher amounts of water extractable organic carbon and a decrease between 3% and 69% in the microbial biomass carbon (using the substrate-induced respiration technique) compared to field moist samples. The magnitude of air-drying and rewetting derived effects on sample characteristics appears to be site and soil type specific.
    Keywords: Soil Analyses ; Air-Drying ; Rewetting ; Soil Organic Matter Characteristics ; Aggregate Stability ; Hydrophobicity ; Agriculture ; Chemistry
    ISSN: 0038-0717
    E-ISSN: 1879-3428
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  • 4
    In: PLoS ONE, 2015, Vol.10(10)
    Description: Antithrombotic therapy consisting of a dual anti-platelet therapy (DAPT) and oral anti-coagulation (OAC) with a vitamin k antagonist is often referred to as triple therapy. This combined anticoagulation is applied in patients undergoing coronary artery stent implantation while also having an indication for OAC. Triple therapy increases the risk for bleeding events compared to either DAPT or OAC alone and thereby might be associated with adverse outcomes. Clinical data on the frequency of bleeding events in patients on triple therapy from clinical trials derives from pre-selected patients and may differ from the real world patients. We report data on patient characteristics and bleeding incidence of patients dismissed on triple therapy from a single university hospital. Within the time span from January 2000 to December 2012, we identified a total of 213 patients undergoing PCI who were prescribed a triple therapy for at least 4 weeks (representing 0.86% of all patients treated). The usage of triple therapy significantly increased over the observed time period. The average CHA 2 DS 2 -VASc Score was 3.1 ± 1.1 with an average HAS-BLED score of 2.5 ± 0.86 representing a high-risk group for thromboembolic events as well as considerable risk for bleeding events. An on-treatment bleeding incidence of 9.4% was detected, with gastrointestinal and airway bleeding being the most frequent (5.1% and 1.4%, respectively). This is consistent with data from clinical trials and confirms the high risk of bleeding in patients on DAPT plus OAC. 29.0% of all patients receiving triple therapy had an indication for OAC other than non-valvular atrial fibrillation. This substantial patient group is underrepresented by clinical trials and needs further attention.
    Keywords: Research Article
    E-ISSN: 1932-6203
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  • 5
    Language: English
    In: Journal of Plant Nutrition and Soil Science, August 2014, Vol.177(4), pp.479-495
    Description: Application of ultrasound to disperse soil aggregates has been critical in enabling researchers to separate and analyze aggregate building blocks that include organic and mineral particles as well as mineral associated organic matter. But the forces generated in the process may also alter the dispersion products and, thus, potentially interfere with the interpretation of experimental results. This review summarizes present knowledge on experimental conditions that may lead to physical damage and chemical modifications of aggregate building blocks. The energy level at which physical disintegration of organic particles could be detected was as low as 60 J mL. Physical damage of sand‐ and silt‐sized mineral particles was observed to commence at energy levels exceeding 700 J cm. No evidence was found for the disintegration of particles within the clay‐size fraction of soils even though studies analyzing pure minerals such as kaolinite revealed particle breakage after application of energy amounts 〉 12,000 J cm. Here we outline a strategy to minimize artifacts such as physical damage of mineral or organic particles resulting from ultrasonication by adopting a stepwise dispersion protocol involving successively higher energy levels, accompanied by a sequential separation of organic and mineral compounds.
    Keywords: Ultrasonication ; Soil Aggregates ; Organic Matter ; Mineral Particles
    ISSN: 1436-8730
    E-ISSN: 1522-2624
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  • 6
    Language: English
    In: American journal of public health, March 2014, Vol.104(3), pp.e85-93
    Description: We examined disparities among US adults with disabilities and the degree to which health insurance attenuates disparities by race, ethnicity, and socioeconomic status (SES). We pooled data from the 2001-2007 Medical Expenditure Panel Survey on individuals with disabilities aged 18 to 64 years. We modeled measures of access and use as functions of predisposing, enabling, need, and contextual factors. We then included health insurance and examined the extent to which it reduced observed differences by race, ethnicity, and SES. We found evidence of disparities in access and use among adults with disabilities. Adjusting for health insurance reduced these disparities most consistently for emergency department use. Uninsured individuals experienced substantially poorer access across most measures, including reporting a usual source of care and experiencing delays in or being unable to obtain care. Although health insurance is an important enabling resource among adults with disabilities, its effect on reducing differences by race, ethnicity, and SES on health care access and use was limited. Research exploring the effects of factors such as patient-provider interactions is warranted.
    Keywords: Healthcare Disparities ; Insurance, Health ; Disabled Persons -- Statistics & Numerical Data ; Insurance Coverage -- Statistics & Numerical Data
    ISSN: 00900036
    E-ISSN: 1541-0048
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  • 7
    Language: English
    In: International Journal of Project Management, January 2015, Vol.33(1), pp.126-139
    Description: Project portfolio management (PPM) is a commonly employed technique to align a project portfolio with strategic goals. Prior research has mainly regarded PPM as a methodology to optimize the overall benefit of a project portfolio. While adequate project selection techniques are certainly important, we argue that successful PPM – and consequently effective strategy implementation – depends on an organization's structural alignment with the needs of PPM. Based on three cases in the German construction industry, we study the effects of fundamental strategic changes on the project selection and organizational structure. From our case analysis, we develop a substantive theory to explain how the criteria, used by a company to choose and evaluate its projects, influence the company's structure through the information requirements created by such criteria. To assess whether our theory is in line with accepted schools of thought on organizational design, we integrate it with existing organizational theories. Our contribution is twofold. First, we offer a substantive theory that integrates strategy implementation, organizational information processing, and structural adaptation. Second, we introduce a new antecedent of successful PPM, namely structural alignment, thus introducing a new perspective on PPM beyond mere project selection techniques.
    Keywords: Strategic Project Portfolio Management ; Contingency Theory ; Theory of Organizational Information Processing ; Engineering
    ISSN: 0263-7863
    E-ISSN: 1873-4634
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  • 8
    Language: English
    In: American journal of public health, May 2014, Vol.104(5), pp.e3-4
    Keywords: Healthcare Disparities ; Insurance, Health ; Disabled Persons -- Statistics & Numerical Data ; Insurance Coverage -- Statistics & Numerical Data
    E-ISSN: 1541-0048
    Source: MEDLINE/PubMed (U.S. National Library of Medicine)
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  • 9
    Language: English
    In: Tenside Surfactants Detergents, 05/15/2014, Vol.51(3), pp.282-285
    Description: ESIFORM Systems are used for surfactants, detergents and other chemicals in order to produce pastilles out of melted products, combining solidification with granulation. These pastilles are opposite to flakes, strips or spraying granulates free of dust, free flowing, easy to fill in and have nearly no tendency at all for blocking or agglomeration as well as they have a higher bulk density with an ideal shape when passing them over to the next step of further processing specially suitable for reliable transport in bulk handling systems such as bagging systems and big-bag filling stations.
    Keywords: Agglomeration ; Tensid ; Schüttdichte ; Waschmittel ; Schüttgut ; Staub ; Granulation ; Spritzen ; Massenguttransport ; Fördermaschine ; Handling-System ; Verarbeitungsanlage ; Tankstelle;
    ISSN: 0932-3414
    E-ISSN: 2195-8564
    Source: CrossRef
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  • 10
    Language: English
    In: Geoderma, 01 February 2016, Vol.263, pp.1-7
    Description: Mineral topsoils possess large organic carbon (OC) contents but there is only limited knowledge on the mechanisms controlling the preservation of organic matter (OM) against microbial decay. Samples were taken from the uppermost mineral topsoil horizon (0 to 5 cm) of seven sites under mature deciduous forest showing OC contents between 69 and 164 g kg and a wide range in mineral characteristics. At first, organic particles and the water-extractable OM were removed from the soil samples. Thereafter, Na-pyrophosphate extractable organic matter (OM(PY)), assumed to be indicative for OM bound via cation mediated interactions, and the OM remaining in the extraction residue (OM(ER)), supposed to be indicative for OM occluded in mechanically highly stable micro-aggregates, were sequentially separated and quantified. The composition of OM(PY) and OM(ER) was analyzed by FTIR and their stability by C measurements. The OC remaining in the extraction residues accounted for 38 to 59% of the bulk soil OC (SOC) suggesting a much larger relevance of OM(ER) for the OM dynamic in the analyzed soils as compared with OM(PY) that accounted for 1.6 to 7.5% of the SOC. The FTIR analyses revealed a lower relative proportion of C O groups in OM(ER) compared to OM(PY) indicating differences in the degree of microbial processing between these fractions. Correlation analyses suggest an increase in the stability of OM(PY) with the soil pH and contents of Na-pyrophosphate soluble Fe, Al, and Mg and an increase in the stability of OM(ER) with the soil pH and the contents of clay and oxalate-soluble Fe and Al. Despite the detected influence of soil mineral characteristics on the turnover of OM(PY) and OM(ER), the Δ C signatures indicated mean residence times less than 100 years. The presence of less stabilized OM in these fractions can be derived from methodological uncertainties and/or the fast cycling compartment of mineral-associated OM.
    Keywords: Forest Mineral Topsoil ; Organic Matter Stabilization ; Na-Pyrophosphate Soluble Organic Matter ; Micro-Aggregates ; Infrared Spectroscopy ; 14c Analyses ; Agriculture
    ISSN: 0016-7061
    E-ISSN: 1872-6259
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