Pedobiochemical indicators for eutrophication and the development of ”︁black spots” in tidal flat soils on the North Sea coast     

Luise Giani  Elke Ahrensfeld 《植物养料与土壤学杂志》2002,165(4):537-543

The increasing eutrophication of tidal flat soils on the North Sea coast and the appearance of ”︁black spots” gave rise to this study. The aim was to find pedobiochemical indicators for the development of ”︁black spots”. Artificially eutrophicated soils were compared with untreated soils in the field and laboratory. The pH values of the artificially eutrophicated and natural soils often differed by nearly one unit. The treated soils mostly showed lower redox potentials (˜ —300 mV) than the untreated samples (˜ —250 mV). The mean sulfate concentrations were 2.2 mM in the eutrophicated laboratory soils and 13.1 mM in the eutrophicated field soils, compared with 12.5 mM and 20.2 mM in the untreated ones. Consequently, the SO₄^2—:Cl^— ratios and SO₄^2— differences were lower in the treated soils. Non‐eutrophicated soils showed methane concentrations of < 5 nmol cm^—3, whereas the eutrophicated soils showed up to 217.0 nmol cm^—3 in the field and 479.1 nmol cm^—3 in the laboratory. Differences between field and laboratory data were mainly due to a continuous sulfate supply and reoxidation process only possible in the field. Although all parameters showed differences between the eutrophicated and untreated soils, only the methane data did not overlap with their interquartile ranges. Those of the untreated soils were 2—7 nmol cm^—3 and those of the treated were 12—360 nmol cm^—3. Thus, threshold values can be defined. Methane concentrations of approximately > 10 nmol cm^—3 refer to the beginning eutrophication process and those in the range of > 100 nmol cm^—3 to advanced processes, phenologically forming ”︁black spots”.  相似文献   

Evaluation of Physicochemical and Glycaemic Properties of Commercial Plant-Based Milk Substitutes     

Stephanie Jeske  Emanuele Zannini  Elke K. Arendt 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(1):26-33

The market for plant-based dairy-type products is growing as consumers replace bovine milk in their diet, for medical reasons or as a lifestyle choice. A screening of 17 different commercial plant-based milk substitutes based on different cereals, nuts and legumes was performed, including the evaluation of physicochemical and glycaemic properties. Half of the analysed samples had low or no protein contents (<0.5 %). Only samples based on soya showed considerable high protein contents, matching the value of cow’s milk (3.7 %). An in-vitro method was used to predict the glycaemic index. In general, the glycaemic index values ranged from 47 for bovine milk to 64 (almond-based) and up to 100 for rice-based samples. Most of the plant-based milk substitutes were highly unstable with separation rates up to 54.39 %/h. This study demonstrated that nutritional and physicochemical properties of plant-based milk substitutes are strongly dependent on the plant source, processing and fortification. Most products showed low nutritional qualities. Therefore, consumer awareness is important when plant-based milk substitutes are used as an alternative to cow’s milk in the diet.  相似文献   

Authenticity assessment of gamma- and delta-decalactone from prunus fruits by gas chromatography combustion/pyrolysis isotope ratio mass spectrometry (GC-C/P-IRMS)     

Tamura H  Appel M  Richling E  Schreier P 《Journal of agricultural and food chemistry》2005,53(13):5397-5401

Authenticity assessment of gamma-decalactone (1) and delta-decalactone (2) from peach (Prunus persica var. persica), apricot (Prunus armeniaca), and nectarine (Prunus persica var. nectarina) was performed using gas chromatography-isotope ratio mass spectrometry (GC-IRMS) in the combustion (C) and pyrolysis (P) mode. In addition, commercially available synthetic (nature-identical) 1 and 2 as well as biotechnologically produced samples (declared to be "natural") were characterized by their delta(2)H(V)(-)(SMOW) and delta(13)C(V)(-)(PDB) values. For the Prunus fruits under study, rather narrow ranges of delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) data of 1, varying from - 34.6 per thousand to - 38.4 per thousand and -160 per thousand to -206 per thousand, respectively, were obtained. Synthetic references of 1 showed delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) data ranging from -27.4 per thousand to -28.3 per thousand and -151 per thousand to -184 per thousand, respectively. Samples of 1 declared to be "natural" exhibited ranges from -28.1 per thousand to -29.2 per thousand and -192 per thousand to -286 per thousand for delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW), respectively. For 2 from peach, apricot, and nectarine, delta(13)C(V)(-)(PDB) values ranging from -34.0 per thousand to -37.9 per thousand were determined; the delta(2)H(V)(-)(SMOW) values ranged from -171 per thousand to -228 per thousand. The delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) data for synthetic 2 were -28.2 per thousand and -171 per thousand, respectively, that is, similar to those of 2 from "natural" origin, ranging from -27.7 per thousand to -30.1 per thousand and -185 per thousand to -230 per thousand for delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW), respectively. GC-C/P-IRMS allowed clear-cut analytical differentiation of the synthetic and "ex-plant" origin of 1 and 2, whereas narrow ranges of delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) data were found for samples of synthetic and "natural" origin.  相似文献   

Von dauerbrache und fruchtfolge auf die n‐bilanzen einer löss‐schwarzerde unter berücksichtigung extremer düngungsvarianten     

Martin Körschens  Elke Schulz  Siegfried Knappe 《Archives of Agronomy and Soil Science》2013,59(6):415-422

In einem zweifaktoriellen Dauerversuch (Anlage 1983/84) auf Löß‐Schwarzerde im Mitteldeutschen Trockengebiet wurde der Einfluß steigender Stalldunggaben bis zu 200t/ha.a auf die N‐Bilanz und die Verlagerung mineralischen Stickstoffs in tiefere Bodenschichten (bis 5 m Tiefe) in einer Fruchtfolge und unter Dauerschwarzbrache untersucht. Ein beträchtlicher Teil des Stickstoffs wurde in 0–60 cm Tiefe in der organischen Substanz des Bodens akkumuliert. Der mineralische Stickstoff ist mit Pflanzenbewuchs bis in eine Tiefe von 0–100 cm, unter Schwarzbrache bis ca. 3m Tiefe zu finden. Die Gefahr hoher gasförmiger N‐Verluste (im vorliegenden Versuch ca. 20%) bzw. von Auswaschungsverlusten beim Brachlegen von Ackerflächen wird durch diese Untersuchungen unterstrichen.  相似文献   

Quantifying rice yield gaps and their causes in Eastern and Southern Africa     

Kalimuthu Senthilkumar  Jonne Rodenburg  Ibnou Dieng  Elke Vandamme  Fitta Silas Sillo  Jean-Martial Johnson  Arisoa Rajaona  Jemima Amielle Ramarolahy  Rene Gasore  Bayuh Belay Abera  Geophrey J. Kajiru  Jerome Mghase  Jimmy Lamo  Raymond Rabeson  Kazuki Saito 《Journal of Agronomy and Crop Science》2020,206(4):478-490

The demand for rice in Eastern and Southern Africa is rapidly increasing because of changes in consumer preferences and urbanization. However, local rice production lags behind consumption, mainly due to low yield levels. In order to set priorities for research and development aimed at improving rice productivity, there is a need to characterize the rice production environments, to quantify rice yield gaps—that is, the difference between average on-farm yield and the best farmers’ yield—and to identify causes of yield gaps. Such information will help identifying and targeting technologies to alleviate the main constraints, and consequently to reduce existing yield gaps. Yield gap surveys were conducted on 357 rice farms at eight sites (19–50 farmers per site) across five rice-producing countries in Eastern and Southern Africa—that is Ethiopia, Madagascar, Rwanda, Tanzania and Uganda—for one or two years (2012–13) to collect both quantitative and qualitative data at field and farm level. Average farm yields measured at the eight sites ranged from 1.8 to 4.3 t/ha and the average yield gap ranged from 0.8 to 3.4 t/ha. Across rice-growing environments, major causes for yield variability were straw management, weeding frequency, growth duration of the variety, weed cover, fertilizer (mineral and organic) application frequency, levelling and iron toxicity. Land levelling increased the yield by 0.74 t/ha, bird control increased the yield by 1.44 t/ha, and sub-optimal management of weeds reduced the yield by 3.6 to 4.4 t/ha. There is great potential to reduce the current rice yield gap in ESA, by focusing on improvements of those crop management practices that address the main site-specific causes for sub-optimal yields.  相似文献   

Determination of 2H/1H and 13C/12C isotope ratios of (E)-methyl cinnamate from different sources using isotope ratio mass spectrometry     

Fink K  Richling E  Heckel F  Schreier P 《Journal of agricultural and food chemistry》2004,52(10):3065-3068

For the authenticity assessment of (E)-methyl cinnamate from different origins, combustion/pyrolysis-isotope ratio mass spectrometry (C/P-IRMS) was used by an elemental analyzer (EA) and on-line capillary gas chromatography coupling (HRGC-C/P-IRMS). For that reason, (E)-methyl cinnamate self-prepared from synthetic, natural, and semisynthetic educts was analyzed in comparison to the commercial synthetic and natural ester. In addition, (E)-methyl cinnamate from basil extract and a number of commercial natural aromas was investigated. The data of self-synthesized synthetic (E)-methyl cinnamate, i.e., delta(13)C(V)(-)(PDB) = -33.8 per thousand and delta(2)H(V)(-)(SMOW) = +349 per thousand, corresponded with that found for the commercial synthetic samples (-29.5 to -31.4 per thousand and +328 to +360 per thousand for delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW), respectively). The ester produced from natural educts by acid as well as Candida antarctica catalysis revealed delta(13)C(V)(-)(PDB) = -25.6 and -30.1 per thousand as well as delta(2)H(V)(-)(SMOW) = -162 and -169 per thousand, respectively. Acid-catalyzed semisynthetic products differed in their delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) values depending on the origin of their educts. For the ester from synthetic methanol and natural cinnamic acid, -27.3 and -126 per thousand were determined for delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW), respectively, whereas for the ester produced from natural methanol and synthetic acid delta(13)C(V)(-)(PDB) = -30.6 per thousand and delta(2)H(V)(-)(SMOW) = +287 per thousand were found. Basil extract showed -28.9 and -133 per thousand for delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW), respectively. Commercial aromas declared to be natural revealed delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) data ranging from -25.7 to -28.5 per thousand as well as -85 to -191 per thousand, respectively, indicating, in part, incorrect declaration.  相似文献   

Effects of Different Cereal Fibers on Cholesterol and Bile Acid Metabolism in the Syrian Golden Hamster     

Drte Rieckhoff  Elke A. Trautwein  Yrj Mlkki  Helmut F. Erbersdobler 《Cereal Chemistry》1999,76(5):788-795

This study examined the effects of various cereal fibers and various amounts of β-glucan on cholesterol and bile acid metabolism. Hamsters were fed semisynthetic diets containing 0.12% cholesterol, 20% fat, and either 16% total dietary fiber (TDF) from wheat bran (control) or 10% TDF from oat bran, 13% TDF from oat bran concentrate or barley grains, 16% TDF from oat fiber concentrate, barley flakes, or rye bran. After five weeks, plasma total cholesterol and liver cholesterol concentrations were significantly lower (20 and 50%, respectively) only in hamsters fed rye bran. Diets containing any of the oat ingredients or barley had no effect on total cholesterol. Changes in the pattern of biliary bile acids occurred in hamsters fed 16% TDF from barley flakes or 10% TDF from oat bran. Hamsters fed rye bran had a significantly higher fecal bile acid excretion when compared with controls fed wheat bran. Because rye bran caused the most pronounced lowering effect of total cholesterol despite the lowest content of β-glucan and soluble fibers, components other than β-glucan and soluble fibers seem to be involved in its hypocholesterolemic action. Since the effects of the oat and barley ingredients were not solely correlated to the β-glucan content, structural changes occurring during processing and concentrating of the products may have impaired the hypocholesterolemic potential of the β-glucans, and other factors such as solubility and viscosity of the fiber components seem to be involved.  相似文献   

Einfluss von Bodenart und langjährig differenzierter düngung auf die Akkumulation und Stabilisierung Organischer Bodensubstanz (OBS) in unterschiedlichen Bodenfraktionen     

Elke Schulz 《Archives of Agronomy and Soil Science》2013,59(5):365-380

Auf der Grundlage der Extremvarianten des Statischen Düngungsversuchs Bad Lauchstädt (Löß‐Schwarzerde, Haplic Chernozem) und des Nährstoffmangelversuchs Thyrow (Tiefiehm‐Fahlerde, Albic Luvisol) wurde der Einfluss langjährig differenzierter Düngung auf die Akkumulation und Stabilisierung von organischer Bodensubstanz (OBS) in unterschiedlichen Bodenfraktionen untersucht. Durch Heißwasserextraktion wird ein Pool leicht umsetzbarer und damit labiler organischer Substanz erfasst. Die kombinierte Korngrößen‐ und Dichtefraktionierung lieferte einen OBS‐Pool, der mit dem Mineralkörper des Bodens (Tonfraktion) assoziiert und dadurch stabilisiert ist bzw. im Falle der Dichtefraktionen einen OBS‐Pool, der nur locker mit dem Mineralkörper verbunden ist. Aus der massenmäßigen Verteilung der Ton‐ und Dichtefraktionen lassen sich sowohl Standort‐ als auch Bewirtschaftungseinflüsse ableiten. Die Betrachtung der C‐Gehalte sowie der C‐Anreicherungsfaktoren der Ton‐ bzw. spezifisch leichten Fraktionen erlauben Aussagen zum Einbau organischer Substanz in unterschiedlich stabilisierte OBS‐Fraktionen. Aus dem Vergleich der beiden Bodenarten wird ersichtlich, dass neben den Umsatzbedingungen (Witterung) auch die Qualität der OBS für deren Umsatz sowie für Transformationsprozesse von Nähr‐ und Schadstoffen eine wesentliche Bedeutung besitzt.  相似文献   

Hypoglycemia and its effect on the brain     

Natara L. Loose  DVM  DACVECC    Elke Rudloff  DVM  DACVECC    Rebecca Kirby  DVM  DACVIM  DACVECC 《Journal of Veterinary Emergency and Critical Care》2008,18(3):223-234

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Utstein‐style guidelines on uniform reporting of in‐hospital cardiopulmonary resuscitation in dogs and cats. A RECOVER statement          下载免费PDF全文

Manuel Boller Dr med vet  MTR  DACVECC  Dan J. Fletcher DVM  PhD  DACVECC  Benjamin M. Brainard VMD  DACVECC  DACVAA  Kate Hopper BVSc  PhD  DACVECC  Vinay M. Nadkarni MD  MS  FCCM  Peter T. Morley MBBS  FRACP  FANZCA  FCICM  FERC  Maureen McMichael DVM  DACVECC  Ryohei Nishimura DVM  PhD  Joris H. Robben DVM  PhD  DECVECC  Elizabeth Rozanski DVM  DACVECC  DACVIM  Elke Rudloff DVM  DACVECC  John Rush DVM  MS  DACVIM  DACVECC  Andre Shih DVM  DACVAA  DACVECC  Sean Smarick VMD  DACVECC  Luis H. Tello MV  MS  DVM 《Journal of Veterinary Emergency and Critical Care》2016,26(1):11-34

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