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A low adenoma detection rate (ADR) increases risks of interval cancers (ICs). Proximal colon flat polyps, e.g. serrated lesions (SLs), are difficult to find. Missed proximal colon flat lesions likely contribute to IC. We compared chromoendoscopy with water exchange (CWE), water exchange (WE) and air insufflation (AI) in detecting adenomas in screening colonoscopy. After split-dose preparation, 480 veterans were randomized to AI, WE and CWE. Primary outcome of proximal ADR (55.6% vs 53.4% vs 52.2%, respectively) were similar in all groups. Adenoma per colonoscopy (APC) and adenoma per positive colonoscopy (APPC) were comparable. Detection rate of proximal colon SLs was significantly higher for CWE and WE than AI (26.3%, 23.6% and 11.3%, respectively, p?=?0.002). Limitations: single operator; SLs only surrogate markers of but not IC. When an endoscopist achieves high-quality AI examinations with overall ADR twice (61.6%) the recommended standard (30%), use of WE and CWE does not produce further improvement in proximal or overall ADR. Comparable APC and APPC confirm equivalent withdrawal inspection techniques. WE alone is sufficient to significantly improve detection of proximal SLs. The impact of increased detection of proximal SLs by WE on prevention of IC deserves to be studied. This study is registered at ClinicalTrial.gov (NCT#01607255).

Ziel des Forschungsprojektes ist die Entwicklung von langzeitstabilen Dickschichtwiderständen mit minimiertem Temperaturkoeffizienten des Widerstandes (TKR) für Spannungssensoren, die bei höchsten Innenwiderständen präzise Spannungsmessungen in Energieübertragungs- und Verteilungsnetzwerken zuverlässig ermöglichen. Die Präzision heutiger Systeme genügt den zukünftigen Anforderungen nicht. Für die nächste Generation der Dickschichtwiderstände für Spannungssensoren ist ein extrem kleiner TKR von 0 ± 3 ppm/K notwendig. Einen vielversprechenden Lösungsansatz für die Herstellung von robusten, intrinsisch temperaturkompensierten und kosteneffizienten Spannungssensoren bietet die Dickschichttechnologie. Dabei wird ein keramischer Funktionswerkstoff in pastöse Form überführt, bevorzugt auf keramische, isolierende Trägermaterialien mittels Siebdruck aufgebracht und anschließend gesintert. Neben der hohen Korrosionsbeständigkeit und Spannungsfestigkeit der Dickschichtwiderstände ermöglicht das Trimmen einen extrem genauen Abgleich des Nennwiderstandswertes. Es wurden Glas-RuO2- basierte Dickschichtwiderstände für Al2O3Substrate entwickelt, welche einen niedrigen TKR aufweisen. Die Änderungen des Flächenwiderstandes und des TKR der gesinterten Schichtwiderstände sind in Abhängigkeit von der Pulverqualität des als leitfähige Phase verwendeten Oxids RuO2sowie der Zusammensetzung des eingesetzten Glases untersucht worden. Des Weiteren wurde die Wirkung des Zusatzes von Additiven als TKR-Modifikatoren geprüft. The aim of the research project is the development of long-term stable thick film resistors with minimal temperature coefficient of resistance (TCR) for voltage sensors that provide precise voltage measurements in power transmission and distribution networks at the highest internal resistances possible. The precision of today’s systems does not meet the future requirements. For the next generation of thick film resistors for voltage sensors, an extremely small TCR of 0 ± 3 ppm/K is necessary. A promising approach for the production of robust, intrinsically temperature compensated and cost-effective power sensors is provided by thick film technology. In this case, a ceramic functional material is transferred into a paste, preferably applied to ceramic insulating substrates by screen printing and then sintered. In addition to high corrosion resistance and dielectric strength of the thick film resistors, trimming enables extremely precise adjustment of the nominal resistance value. Glass-RuO2-based thick film resistors were developed for Al2O3substrates, which have a low TCR. The changes of the surface resistance and the TCR of the sintered resistors have been investigated as a function of the quality of the oxide powder used as the conductive phase (RuO2) and the composition of the glass used. Furthermore, the effect of the addition of additives as TCR modifiers was investigated.

The dynamics of carbon (C) and nitrogen (N) of plant residues and organic fertilisers are of great interest for agricultural and global warming studies. The proportion of the fractions obtained from biochemical analyses (fibres by sequential Van Soest analysis) can be used for predicting both C and N transformation of organic materials in soils. Considering the expensive and time-consuming Van Soest method, the principal aim of this study was to elaborate near infrared (NIR) calibrations for fibres, in order to use them for consecutive studies (for example, our works on transformation of added organics or TAO model). A wide set of organic fertilisers and their raw materials was sampled, including plant materials originating from temperate (especially Mediterranean) and tropical regions. The particular objective of this work was to build NIR calibrations for fibre fractions, along with C and N content, in plant materials used in the organic fertiliser industry and green house gases mitigating strategies. The second particular objective was to test for two levels of validation of the equations previously elaborated: (1) validation with a set of randomly chosen samples that was not considered during the calibration step, (2) extrapolation of the predictive capacity of the equations when applying them to outliers that were previously discarded. The fibres were the best predicted parameters, as R² = 0.95, 0.91, 0.97, 0.97 for neutral detergent soluble, hemicelluloses, cellulose and lignin, respectively, whereas the characteristics of total organic matter had R² varying from 0.87 (N Kjeldahl) to 0.94 (C Dumas). The accuracy of the calibrations developed for fibres was confirmed by the first level of validation, since the standard errors of prediction were close to the corresponding standard errors of cross-validation and the standard errors of calibration. Nevertheless, the calibrations developed for ash and C Dumas were not so good. Surprisingly, at the second level of validation, some outliers were not so badly predicted. This can illustrate the robustness of the calibrations for cellulose, lignin and, to a lesser extent, N Dumas which are key parameters for our modelling works on C and N transformation of added organics in soils.

Some general notions on soil organic carbon (SOC) sequestration and the difficulties to evaluate this process globally are presented. Problems of time- and space- scales are emphasized. SOC erosion, which is generally difficult to evaluate in relation to land use changes, is discussed in detail. Different aspects of SOC sequestration on the Lesser Antilles are presented for a wide range of soil types. Comparisons between soils revealed that the SOC stocks in the Lesser Antilles are highly dependent upon the mineralogy: higher stocks for allophanic (ALL) soils than for low activity clay (LAC) and high activity clay (HAC) soils. But in terms of potential of SOC sequestration (pSeq-SOC, differences between permanent vegetation and continuous cultivation situations), there are no differences between ALL and LAC soils (22.9 and 23.3 tC. ha−1, respectively). On the other hand, the potentials of SOC sequestration were higher for HAC soils (30.8 – 59.4 tC. ha−1, with the higher levels in the less Mg- and Na-affected Vertisol). Sheet erosion is a serious problem for Vertisol with high Mg and Na on exchange complex, causing high dispersability of fine elements. Thus, the lower SOC levels in these soils may be partly due to erosion losses. Laboratory incubations have shown that 37 – 53% of the protected SOC in these soils was located in aggregates larger than 0.2 mm. The effect of agricultural practices on SOC sequestration was studied for the Vertisols. Intensification of pastures led to higher plant productivity and higher organic matter restitutions and SOC sequestration. The gain was 53.5 and 25.4 tC. ha−1for the low and high-Mg Vertisol, respectively (0–20 cm layer). SOC sequestration with pastures also depends upon the plot history with lower mean annual increase in SOC for the initially eroded (1.0 gC . kg−1soil . yr−1) than for the non-degraded (1.5 gC . kg−1soil . yr−1) Vertisol. Loss of SOC in a pasture-market gardening rotation was 22.2 tC . ha−1with deep (30–40 cm) and 10.7 tC . ha−1with surface (10–15 cm) tillage. It was unclear whether the differences in SOC losses were due to mineralization and/or to erosion.

Carbon mineralization kinetics of 17 organic materials were studied in a Mediterranean sandy soil. These added organic matters (AOM) used in the organic fertilizer industry differed in their origin and composition: plant residues from the agri-food industry, animal wastes, manures (plant and animal origin), composts at different composting times and organic fertilizers. The mixtures AOM-soils were incubated under aerobic conditions at 28°C during 6 months. Soil moisture was maintained at 75% water holding capacity and respired-CO2was regularly trapped into alkali media in closed chambers, then checked by HCl titration. Analyses of CO2were performed in triplicate at 17 sampling occasions. The mineralized AOM fraction (MAOMF) varied according to the AOM origin: from 12–33% of added C for composts, to 65–90% for animal-originated AOM, with many intermediate patterns for plant-originated AOM.

Abstract:  The effects of a composted organic amendment and solarization on the organic matter (OM) of a sandy soil were determined by means of particle-size fractionation and analysis of carbon and nitrogen contents. After 2 years, total soil carbon increased under organic fertilization but did not significantly change with solarization. As a consequence of the climatic conditions in the greenhouse, the carbon concentrations (g kg–1 fraction) of the particle-size fractions were lower than those found for temperate soils and closer to those for tropical soils. The carbon amounts (g kg–1 soil) and carbon:nitrogen ratios, which were highest in fractions >200 μm, reflected the short-term influence of the industrially processed organic amendment, rich in composted coarse plant debris. In contrast, the characteristics of the OM associated with each fraction were not significantly affected by solarization. In comparison with other coarse-textured temperate or tropical soils, carbon concentrations in fine silt (2–20 μm) and clay (0–2 μm) fractions were very low. This suggests a "greenhouse effect", together with a high rate of carbon mineralization affecting fine silt and clay fractions.

The fate of N when incorporated in a ferrallitic soil was investigated during a 3-month incubation, using either 15N-labelled urea or 15N-labelled crop residues (sugarcane roots and leaves). The organic matter was characterized by particle-size fractionation. The urea-derived organic 15N was mainly found in the clay-sized fractions and was ascribed to biological activity. The plant-derived 15N was observed both in the sand-sized and in the clay-sized fractions; the former pool was ascribed to the persistence of crops residues, the latter to biological immobilization. The relative proportions of organic 15N recovered in the various clay fractions (coarse, fine, and very fine) were similar, irrespective of the nature of the added 15N. The very fine clay fraction (F<0.05 µm) showed the highest isotopic excess, and thus gave rise to the highest turnover rate.

Soil carbon (C) distribution, natural 13C abundances and their changes as a consequence of cropping were studied in three neighboring areas on an Oxisol from Brazil. One site (T0) was under forest, while the two other sites (T12and T50) had been deforested, then cultivated with sugar cane for 12 and 50 yr, respectively. Soil morphological, chemical and mineralogical characteristics in all three sites were very similar. Total C content of the 0.06‐m layer of T0was twice that of T12and T50, then decreased sharply with depth, to values similar to the other profiles. Delta 13C had practically constant values of −25.1, −22.8, and −20.4‰, throughout the 0 to 0.30‐m layer of T0, T12, and T50respectively. These values increased in deeper layers, to about −17‰, due to increased humification and possibly to deposition of organic matter from a former 13C‐rich vegetation. The 0.10‐ to 0.20‐m layer was separated into particle‐size fractions and alkaline extract. Carbon contents decreased from T0to T50in the sand‐size fractions and alkaline extracts, but did not change in the clay‐size fractions. Delta 13C values were used to estimate the proportions of C derived from forest (Cdff) and from sugar cane (Cdfc). Carbon derived from sugar cane represented 17.3 ± 3.2% and 40.5 ± 2.2% of total C in T12and T50, respectively. It reached its maximum value (67 ± 3.7%) in the coarse sand fraction of T12and T50and decreased with decreasing fraction size, to 13.8 ± 9.4% and 30.5 ± 6.5% in the fine clay fractions of T12and T50, respectively. Thus, Cdff persisted mainly in the clay‐size fraction.

Spectroscopic properties of dimers, hydrides, oxides, fluorides and sulphides of the elements In, Sn and Sb have been calculated using energy-adjusted pseudopotentials. Results are given for bond lengths Re, dissociation energies De, vibrational frequencies ωe and dipole moments μe of the ground states. Comparison is made both with experimental and theoretical values, where available. The influence of core-core overlap, of valence correlation as well as of core-valence correlation is discussed. For In2, three low-lying states have been investigated. Contrary to experimental results, the ground state of In2 is found to be 3Π. Ionization potentials of In, Sn, Sb and electron affinities of O, F, S have also been calculated.

Experimental examples of different beta-lactam-organism combinations in vitro and in vivo are presented to demonstrate that a rationale for dosage regimens of antibiotics should not be based solely on pharmacokinetic parameters. The time course of the pharmacological response (onset and speed of bacterial killing) and the presence or absence of a postantibiotic effect must also be considered. Such pertinent information can be derived from in vitro studies such as time-kill curves and regrowth curves of bacteria obtained at and after short exposure of the target organisms to various concentrations of the drug.

Examines the double standard revealed in an article published in UCLA's African-American newspaper, and the campus' reaction, or lack of it. The breaking down of institutional barriers that had impeded the social progress of Jews; Jews as the invisible ethnic group; The paradox facing young Jewish Americans; More. INSET: United front against racism..

When calculating fertiliser recommendations and nutrient balances, growers and advisers usually do not do site specific measurements but use data from look up tables. Data given by older literature sources, however, do not take into account today's cropping practices. Therefore a databank on nutrient contents of total yields, marketable yields and harvest residues of 22 field vegetable crops is presented. This databank was compiled using results from topical field experiments and from recent literature.

The influence of dosing intervals on the activity of gentamicin and ticarcillin against Pseudomonas aeruginosa was studied in vivo. Granulocytopenic mice infected with P. aeruginosa in the thigh muscle were treated with l-hr or 3-hr injections of gentamicin, ticarcillin, or gentamicin-ticarcillin. Plasma pharmacokinetics of the drugs were correlated with antibacterial activity. Gentamicin injected every 1 hr tended to be less active than gentamicin injected at longer intervals. In contrast, ticarcillin given every 1 hr was significantly more efficacious than equivalent total doses injected every 3 hr. The dosing schedule of gentamicin-ticarcillin was again important for ticarcillin but did not appreciably affect the antibacterial activity of gentamicin. Thus, antimicrobial chemotherapy of P. aeruginosa infections in the granulocytopenic host might be improved by administering ticarcillin rather than gentamicin as a constant infusion.