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  • 1
    Language: English
    In: Science (New York, N.Y.), 10 September 2010, Vol.329(5997), pp.1318-9
    Description: Chlorophylls are essential for light-harvesting and energy transduction in photosynthesis. Four chemically distinct varieties have been known for the past 60 years. Here we report isolation of a fifth, which we designate chlorophyll f. Its in vitro absorption (706 nanometers) and fluorescence (722 nanometers) maxima are red-shifted compared to all other chlorophylls from oxygenic phototrophs. On the basis of the optical, mass, and nuclear magnetic resonance spectra, we propose that chlorophyll f is [2-formyl]-chlorophyll a (C55H70O6N4Mg). This finding suggests that oxygenic photosynthesis can be extended further into the infrared region and may open associated bioenergy applications.
    Keywords: Bacteriochlorophylls -- Chemistry ; Cyanobacteria -- Chemistry ; Pigments, Biological -- Chemistry
    ISSN: 00368075
    E-ISSN: 1095-9203
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  • 2
    In: BJOG: An International Journal of Obstetrics & Gynaecology, November 2018, Vol.125(12), pp.1540-1540
    Description: To purchase or authenticate to the full-text of this article, please visit this link: http://onlinelibrary.wiley.com/doi/10.1111/1471-0528.15280/abstract Byline: K Schliep ***** No abstract is available for this article. ***** Article Note: Linked article: This is a mini commentary on A Righarts et al., pp. 1532-1539 in this issue. To view this article visit https://doi.org/10.1111/1471-0528.15247 CAPTION(S):
    Keywords: Pain ; Patient Assessment ; Pain Management ; Gynecology ; Medical Research;
    ISSN: 1470-0328
    E-ISSN: 1471-0528
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  • 3
    In: BJOG: An International Journal of Obstetrics & Gynaecology, November 2016, Vol.123(12), pp.2018-2018
    Description: To purchase or authenticate to the full-text of this article, please visit this link: http://onlinelibrary.wiley.com/doi/10.1111/1471-0528.14168/abstract Byline: KC Schliep ***** No abstract is available for this article. ***** Article Note: Linked article: This is a mini commentary on BZ Shachar et al., pp. 2009-2017 in this issue. To view this article visit http://dx.doi.org/10.1111/1471-0528.14165. CAPTION(S):
    Keywords: Premature Infants;
    ISSN: 1470-0328
    E-ISSN: 1471-0528
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  • 4
    Language: English
    In: American Journal of Clinical Nutrition, 2015, Vol.102(4), p.933(10)
    Description: Background: Although habitual low-to-moderate alcohol intake has been linked with reduced all-cause mortality and morbidity, the effect of recent alcohol intake on female reproductive function has not been clearly established. Objective: We assessed the relation between acute alcohol consumption, reproductive hormones, and markers of menstrual cycle dysfunction including sporadic anovulation, irregular cycle length, luteal phase deficiency, long menses, and heavy blood loss. Design: A total of 259 healthy, premenopausal women from Western New York were followed for [less than or equal to]2 menstrual cycles (2005-2007) and provided fasting blood specimens during [less than or equal to]8 visits/cycle and four 24-h dietary recalls/cycle. Linear mixed models were used to estimate associations between previous day's alcohol intake and hormone concentrations, whereas Poisson regression was used to assess RR of cycle-average alcohol intake and menstrual cycle function. Results: For every alcoholic drink consumed, the geometric mean total and free estradiol, total and free testosterone, and luteinizing hormone were higher by 5.26% (95% CI: 1.27%, 9.41%), 5.82% (95% CI: 1.81%, 9.99%), 1.56% (95% CI: 0.23%, 2.90%), 1.42% (95% CI: 0.02%, 2.84%), and 6.18% (95% CI: 2.02%, 10.52%), respectively, after adjustment for age, race, percentage of body fat, perceived stress, pain- medication use, sexual activity, caffeine, and sleep. Binge compared with nonbinge drinking (defined as reporting 〉4 compared with 〈4 drinks/d, respectively) was associated with 64.35% (95% CI: 18.09%, 128.71%) and 63.53% (95% CI: 17.41%, 127.73%) higher total and free estradiol. No statistically significant associations were shown between cycle-average alcohol intake and menstrual cycle function. Conclusion: Although recent moderate alcohol intake does not appear to have adverse short-term effects on menstrual cycle function, including sporadic anovulation, potential protective and deleterious long-term effects of alterations in reproductive hormones on other chronic diseases warrant additional investigation. Keywords: alcohol, estradiol, menstrual cycle, ovulation, progesterone doi: 10.3945/ajcn.114.102160
    Keywords: Pituitary Hormones – Analysis ; Testosterone – Analysis ; Estrogens – Analysis ; Menstruation – Analysis ; Drinking (Alcoholic Beverages) – Analysis ; Alcoholic Beverages – Analysis ; Glycoproteins – Analysis ; Mortality – Analysis
    ISSN: 0002-9165
    Source: Cengage Learning, Inc.
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  • 5
    Language: English
    In: The American journal of clinical nutrition, March 2013, Vol.97(3), pp.621-30
    Description: Energy-containing beverages are widely consumed among premenopausal women, but their association with reproductive hormones is not well understood. The objective was to assess the association of energy-containing beverages, added sugars, and total fructose intake with reproductive hormones among ovulatory cycles and sporadic anovulation in healthy premenopausal women. Women (n = 259) in the BioCycle Study were followed for up to 2 menstrual cycles; they provided fasting blood specimens during up to 8 visits/cycle and four 24-h dietary recalls/cycle. Women who consumed ≥1 cup (1 cup = 237 mL) sweetened soda/d had 16.3% higher estradiol concentrations compared with women who consumed less sweetened soda (86.5 pg/mL compared with 74.4 pg/mL, P = 0.01) after adjustment for age, BMI, race, dietary factors, and physical activity. Similarly elevated estradiol concentrations were found for ≥1 cup cola/d and noncola soda intake. Neither artificially sweetened soda nor fruit juice intake ≥1 cup/d was significantly associated with reproductive hormones. Added sugar above the average US woman's intake (≥73.2 g/d) or above the 66th percentile in total fructose intake (≥41.5 g/d) was associated with significantly elevated estradiol but not consistently across all models. No associations were found between beverages, added sugars, or total fructose intake and anovulation after multivariate adjustment. Even at moderate consumption amounts, sweetened soda is associated with elevated follicular estradiol concentrations among premenopausal women but does not appear to affect ovulatory function. Further research into the mechanism driving the association between energy-containing beverages and reproductive hormones, and its potential implications for women's health, is warranted.
    Keywords: Beverages -- Analysis ; Ovarian Follicle -- Drug Effects ; Reproduction -- Drug Effects
    ISSN: 00029165
    E-ISSN: 1938-3207
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  • 6
    Language: English
    In: The American journal of clinical nutrition, February 2012, Vol.95(2), pp.488-97
    Description: Caffeinated beverages are widely consumed among women of reproductive age, but their association with reproductive hormones, and whether race modifies any such associations, is not well understood. We assessed the relation between caffeine and caffeinated beverage intake and reproductive hormones in healthy premenopausal women and evaluated the potential effect modification by race. Participants (n = 259) were followed for up to 2 menstrual cycles and provided fasting blood specimens for hormonal assessment at up to 8 visits per cycle and four 24-h dietary recalls per cycle. Weighted linear mixed models and nonlinear mixed models with harmonic terms were used to estimate associations between caffeine and hormone concentrations, adjusted for age, adiposity, physical activity, energy and alcohol intakes, and perceived stress. On the basis of a priori assumptions, an interaction between race and caffeine was tested, and stratified results are presented. Caffeine intake ≥200 mg/d was inversely associated with free estradiol concentrations among white women (β = -0.15; 95% CI: -0.26, -0.05) and positively associated among Asian women (β = 0.61; 95% CI: 0.31, 0.92). Caffeinated soda intake and green tea intake ≥1 cup/d (1 cup = 240 mL) were positively associated with free estradiol concentrations among all races: β = 0.14 (95% CI: 0.06, 0.22) and β = 0.26 (95% CI: 0.07, 0.45), respectively. Moderate consumption of caffeine was associated with reduced estradiol concentrations among white women, whereas caffeinated soda and green tea intakes were associated with increased estradiol concentrations among all races. Further research is warranted on the association between caffeine and caffeinated beverages and reproductive hormones and whether these relations differ by race.
    Keywords: Beverages ; Diet ; Caffeine -- Pharmacology ; Estradiol -- Blood ; Plant Extracts -- Pharmacology
    ISSN: 00029165
    E-ISSN: 1938-3207
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  • 7
    In: Limnology and Oceanography, November 2018, Vol.63(6), pp.2372-2383
    Description: Empirical nutrient models that describe lake nutrient, productivity, and water clarity relationships among lakes play a prominent role in limnology. Landscape‐based regressions are also used to understand macroscale variability of lake nutrients, clarity, and productivity (hereafter referred to as nutrient‐productivity). Predictions from both models are used to inform eutrophication management globally. To date, these two classes of models are generally conducted separately, which ignores the known dependencies among nutrient‐productivity variables. We present a statistical model that integrates nutrient‐productivity and landscape‐based regressions—where lake nutrients, productivity, and clarity variables are modeled jointly. We fitted a joint nutrient‐productivity model to over 7000 lakes with three nutrients (total phosphorus, total nitrogen, nitrate concentrations), chlorophyll concentrations, and Secchi disk depth as response variables and landscape features as predictor variables. Because lakes in different regions respond to landscape features differently, we focused our analysis on two subregions with different dominant land uses, the agricultural Midwest and the forested Northeast U.S. Predictive performance was enhanced by modeling nutrient‐productivity variables jointly. We also found strong evidence that nutrient‐productivity variables were coupled, and that only nitrate may be decoupled from other nutrient‐productivity variables in the forested region. We speculate that these regional differences may be related to differences in the strength of biogeochemical cycles and stoichiometric controls between these regions. Jointly modeling nutrient‐productivity variables in lakes effectively integrates the two dominant approaches for studying lakes nutrient‐productivity relationships and provides novel insight into macroscale patterns of the coupling of nutrients, chlorophyll, and water clarity in lakes.
    ISSN: 0024-3590
    ISSN: Limnology and Oceanography
    E-ISSN: 1939-5590
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  • 8
    Language: English
    In: Applied Physics Letters, 29 May 2017, Vol.110(22)
    Description: We report the demonstration of picosecond Fresnel imaging with an ultrafast transmission electron microscope (UEM). By operating with a low instrument repetition rate (5 kHz) and without objective-lens excitation, the picosecond demagnetization of an FePt film, via in situ , femtosecond laser excitation, is directly imaged. The dynamics are quantified and monitored as a time-dependent change in the degree of electron coherence within the magnetic domain walls. The relative coherence of conventional (thermionic) Fresnel transmission electron microscopy is also directly compared to that of Fresnel UEM through the domain-wall size. Further, the robustness and reversibility of the domain-wall dynamics are illustrated by repeating the picosecond image scans at defocus values having the same magnitude but different signs (e.g., +25 mm vs. −25 mm). Control experiments and approaches to identifying and isolating systematic errors and sources of artifacts are also described. This work, and continued future developments also described here, opens the way to direct correlation of transient structure, morphology, and magnetic dynamics in magnetic thin films and spintronic devices.
    Keywords: Magnetics And Spintronics
    ISSN: 0003-6951
    E-ISSN: 1077-3118
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  • 9
    Language: English
    In: Science, 09/10/2010, Vol.329(5997), pp.1318-1319
    ISSN: 0036-8075
    E-ISSN: 1095-9203
    Source: American Association for the Advancement of Science (via CrossRef)
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  • 10
    Language: English
    In: Computational Statistics and Data Analysis, 2015, Vol.90, p.1(14)
    Description: To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.csda.2015.03.020 Byline: Erin M. Schliep, Jennifer A. Hoeting Abstract: Data augmentation and parameter expansion can lead to improved iterative sampling algorithms for Markov chain Monte Carlo (MCMC). Data augmentation allows for simpler and more feasible simulation from a posterior distribution. Parameter expansion accelerates convergence of iterative sampling algorithms by increasing the parameter space. Data augmentation and parameter-expanded data augmentation MCMC algorithms are proposed for fitting probit models for independent ordinal response data. The algorithms are extended for fitting probit linear mixed models for spatially correlated ordinal data. The effectiveness of data augmentation and parameter-expanded data augmentation is illustrated using the probit model and ordinal response data, however, the approach can be used broadly across model and data types. Article History: Received 28 November 2013; Revised 29 March 2015; Accepted 30 March 2015
    Keywords: Monte Carlo Methods – Analysis ; Algorithms – Analysis
    ISSN: 0167-9473
    Source: Cengage Learning, Inc.
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