687 research outputs found

    Study of odd-mass N=82 isotones with realistic effective interactions

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    The microscopic quasiparticle-phonon model, MQPM, is used to study the energy spectra of the odd Z=5363Z=53 - 63, N=82 isotones. The results are compared with experimental data, with the extreme quasiparticle-phonon limit and with the results of an unrestricted 2s1d0g7/20h11/22s1d0g_{7/2}0h_{11/2} shell model (SM) calculation. The interaction used in these calculations is a realistic two-body G-matrix interaction derived from modern meson-exchange potential models for the nucleon-nucleon interaction. For the shell model all the two-body matrix elements are renormalized by the Q^\hat{Q}-box method whereas for the MQPM the effective interaction is defined by the G-matrix.Comment: Elsevier latex style espart, 26 pages, submitted to Nuclear Physics

    Potential uptake of dissolved organic matter by seagrasses and macroalgae

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    Dissolved organic nitrogen (DON) acts as a large reservoir of fixed nitrogen. Whereas DON utilization is common in the microbial community, little is known about utilization by macrophytes. We investigated the ability of the coexisting temperate marine macrophytes Zostera noltii, Cymodocea nodosa, and Caulerpa prolifera to take up nitrogen and carbon from small organic substrates of different molecular complexities (urea, glycine, L-leucine, and L-phenylalanine) and from dissolved organic matter (DOM) derived from algal and bacterial cultures (substrates with a complex composition). In addition to inorganic nitrogen, nitrogen from small organic substrates could be taken up in significant amounts by all macrophytes. Substrate uptake by the aboveground tissue differed from that of the belowground tissue. No relationships between carbon and nitrogen uptake of small organics were found. The preference for individual organic substrates was related to their structural complexity and C:N ratio. Uptake of algae-derived organic nitrogen was of similar magnitude as inorganic nitrogen, and was preferred over bacteria-derived nitrogen. These results add to the growing evidence that direct or quick indirect DON utilization may be more widespread among aquatic macrophytes than traditionally thought.This research was supported by the regional government of Andalusia project FUNDIV (P07-RNM-2516), the Spanish Project CTM2008-00012/MAR, a European Reintegration Grant (MERG-CT-2007-205675), a travel grant from Schure-Beijerinck-Popping Fund (SBP/JK/2007-32) and the Netherlands Organization for Scientific Research. Thanks to Fidel Echevarrìa Navas (Director of CACYTMAR) for granting us access to facilities, and to Bas Koutstaal for helping with sample processing. We also thank the anonymous reviewers for their valuable comments which significantly improved this manuscript

    Turn the tide: scientific research towards an integrated plan for the Upper-Seascheldt

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    During the last 150 years the Scheldt estuary has seen many changes either to claim land for urban or agricultural development or to improve the navigability. From the 1950’s onwards the most important changes to the character of the estuary could be attributed to infrastructural works such as dike construction and deepening. Even though cause–effect relationships are difficult to determine it is largely accepted that, besides reclamations, the main contribution to the loss of habitat can be attributed to the increase in tidal amplitude. In various studies the relationship between tidal amplification and large scale engineering works, including deepening, (downstream) sand extraction, embankments and straightening works, has been pointed out. It is clear that anthropogenic changes to the system can have serious consequences to the state of the estuary and that future works need to be prepared in a conscious and sustainable manner in order to avoid further tidal amplification.Within the framework of the project “Integrated Plan Upper-Seascheldt” commissioned by the Seascheldt division of the Waterwegen & Zeekanaal NV, it is investigated how navigability can be improved (to class Va) without negative effects to nature and safety against flooding. It is the goal of this integrated study to look for synergy in order to mitigate negative impacts of the proposed measures or even to improve the functioning of the system. In the last 10 years already various environmental measures like de-poldering are being implemented under the SIGMA-Plan.This paper will discuss the evolution of the Seascheldt in relation to historical anthropogenic changes. It will focus on the observed changes in water level, bathymetry, habitats (salt marshes) and sediment concentrations. In addition, the paper will outline the project plan to investigate whether de-poldering projects and other solutions or strategies can be identified that may ‘turn the tide’. This study involves applied scientific research to improve knowledge on (ecological) functioning of the Scheldt Estuary by means of a chain of model developments by the project partners (INBO, UA and FHR)

    Body Size and Colorectal Cancer Risk After 16.3 Years of Follow-up: An Analysis From the Netherlands Cohort Study

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    A large body size may differentially influence risk of colorectal cancer (CRC) by anatomic location. The Netherlands Cohort Study includes 120,852 men and women aged 55-69 years who self-reported weight, height, and trouser/skirt size at baseline (1986), as well as weight at age 20 years. Derived variables included body mass index (BMI; weight (kg)/height (m)2), BMI at age 20 years, and BMI change. After 16.3 years of follow-up (1986-2002), 2,316 CRC cases were available for case-cohort analysis. In men, the highest risk estimates were observed for body fat (per 5-unit increase in BMI, hazard ratio (HR) = 1.25, 95% confidence interval (CI): 1.05, 1.46; for highest quintile of trouser size vs. lowest, HR = 1.63, 95% CI: 1.17, 2.29 (P-trend = 0.02)) and appeared more closely associated with distal colon tumors (for BMI (5-unit increase), HR = 1.42, 95% CI: 1.13, 1.79; for highest quintile of trouser size, HR = 2.56, 95% CI: 1.55, 4.24 (P-trend < 0.01)) than with proximal colon or rectal tumors. In women, body fat was not associated with CRC risk unless it was considered simultaneously with physical activity; a large trouser/skirt size and a low level of physical activity increased risk for all subtypes. Height was associated with risk of CRC, especially distal colon tumors (highest quintile vs. lowest: HR = 1.53, 95% CI: 1.03, 2.27; P-trend = 0.05), in women only. © 2011 The Author

    Diagnostic DNA Methylation Biomarkers for Renal Cell Carcinoma:A Systematic Review

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    CONTEXT: The 5-yr survival of early-stage renal cell carcinoma (RCC) is approximately 93%, but once metastasised, the 5-yr survival plummets to 12%, indicating that early RCC detection is crucial to improvement in survival. DNA methylation biomarkers have been suggested to be of potential diagnostic value; however, their current state of clinical translation is unclear and a comprehensive overview is lacking. OBJECTIVE: To systematically review and summarise all literature regarding diagnostic DNA methylation biomarkers for RCC. EVIDENCE ACQUISITION: We performed a systematic literature review of PubMed, EMBASE, Medline, and Google Scholar up to January 2019, according to the Preferred Reporting Items for Systematic Review and Meta-Analysis of Diagnostic Test Accuracy Studies (PRISMA-DTA) guidelines. Included studies were scored according to the Standards for Reporting of Diagnostic Accuracy Studies (STARD) criteria. Forest plots were generated to summarise diagnostic performance of all biomarkers. Level of evidence (LoE) and potential risk of bias were determined for all included studies. EVIDENCE SYNTHESIS: After selection, 19 articles reporting on 44 diagnostic DNA methylation biomarkers and 11 multimarker panels were included; however, only 15 biomarkers were independently validated. STARD scores varied from 4 to 13 out of 23 points, with a median of 10 points. Large variation in subgroups, methods, and primer locations was observed. None of the reported biomarkers exceeded LoE III, and the majority of studies reported inadequately. CONCLUSIONS: None of the reported biomarkers exceeded LoE III, indicating their limited clinical utility. Moreover, study reproducibility and further development of these RCC biomarkers are greatly hampered by inadequate reporting. PATIENT SUMMARY: In this report, we reviewed whether specific biomarkers could be used to diagnose the most common form of kidney cancer. We conclude that due to limited evidence and reporting inconsistencies, none of these biomarkers can be used in clinical practice, and further development towards clinical use is hindered

    Standardized ADOS Scores: Measuring Severity of Autism Spectrum Disorders in a Dutch Sample

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    The validity of the calibrated severity scores on the ADOS as reported by Gotham et al. (J Autism Dev Disord 39: 693–705, 2009), was investigated in an independent sample of 1248 Dutch children with 1455 ADOS administrations (modules 1, 2 and 3). The greater comparability between ADOS administrations at different times, ages and in different modules, as reached by Gotham et al. with the calibrated severity measures, seems to be corroborated by the current study for module 1 and to a lesser extent for module 3. For module 2, the calibrated severity scores need to be further investigated within a sample that resembles Gotham’s sample in age and level of verbal functioning

    Computer vision enables short- and long-term analysis of <i>Lophelia pertusa</i> polyp behaviour and colour from an underwater observatory

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    An array of sensors, including an HD camera mounted on a Fixed Underwater Observatory (FUO) were used to monitor a cold-water coral (Lophelia pertusa) reef in the Lofoten-Vesterålen area from April to November 2015. Image processing and deep learning enabled extraction of time series describing changes in coral colour and polyp activity (feeding). The image data was analysed together with data from the other sensors from the same period, to provide new insights into the short- and long-term dynamics in polyp features. The results indicate that diurnal variations and tidal current influenced polyp activity, by controlling the food supply. On a longer time-scale, the coral’s tissue colour changed from white in the spring to slightly red during the summer months, which can be explained by a seasonal change in food supply. Our work shows, that using an effective integrative computational approach, the image time series is a new and rich source of information to understand and monitor the dynamics in underwater environments due to the high temporal resolution and coverage enabled with FUOs

    The role of hydrodynamics in structuring in situ ammonium uptake within a submerged macrophyte community

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    In low-nutrient, macrophyte-dominated coastal zones, benthic ammonium (NH4+) uptake may be influencedby the structural properties of plant canopies via their effect on near-bed hydrodynamics. Using adual-tracer (uranine and 15NH4+) method that does not require enclosures, we examined how this processaffects nutrient uptake rates within a tidally dominated, patchy Caulerpa prolifera–Cymodocea nodosalandscape. NH4+ uptake was determined by calculating tissue 15N excesses and correcting for 15N enrichmentas derived from uranine concentration. Vertical hydrodynamic profiles were measured in thedownstream flow direction from outside to inside of the C. nodosa bed by using an array of acousticDoppler velocimeters. The transition from a C. prolifera to a C. nodosa bed included a change in bothbenthic canopy properties (short and dense to tall and sparse) and sediment topography (0.2-m increasein water column depth) that resulted in an increase in longitudinal advection and turbulent diffusivitywithin the C. nodosa canopy between 0.5 and 1.5mfrom the leading edge. Vertical differences in canopywater exchange appeared to explain variations in uptake between biotic functional groups; however, noclear differences in longitudinal uptake were found. Using in situ labeling, this study demonstrated for thefirst time the role of hydrodynamics in structuring NH4+ uptake within an undisturbed, patchy macrophytelandscape

    МОДЕЛИРОВАНИЕ ПРОЦЕССОВ ДОСТАВКИ ВСПОМОГАТЕЛЬНыХ ГРУЗОПОТОКОВ ВНУТРИШАХТНОГО ТРАНСПОРТА С УЧЕТОМ ХАРАКТЕРИСТИКИ ТРАССы

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    Розглянуто специфічні задачі внутрішахтного транспорту. Запропоновано використовувати метод Флойду-Уоршелла для моделювання допоміжних вантажопотоків з урахуванням характеристики мар- шруту. Наведені результати застосування цього методу для своєчасної доставки матеріальних потоків вугільних шахт у підготовчі вибої. Рассмотрены специфические задачи внутришахтного транспорта. Предложено использовать метод Флойда – Уоршелла для моделирования вспомогательных грузопотоков с учетом характеристики трас- сы. Приведены результаты применения используемого метода для оперативной доставки материаль- ных потоков угольных шахт в подготовительные забои
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