Search Results - (Author, Cooperation:G. Berggren)

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  1. 1
    Staff View
    Publication Date:
    2013-06-28
    Publisher:
    Nature Publishing Group (NPG)
    Print ISSN:
    0028-0836
    Electronic ISSN:
    1476-4687
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Apoproteins/chemistry/metabolism ; Biocatalysis ; Biomimetic Materials/*chemical synthesis/*metabolism ; Biomimetics ; Catalytic Domain ; Chlamydomonas reinhardtii/*enzymology ; Clostridium acetobutylicum/genetics/metabolism ; Electron Spin Resonance Spectroscopy ; Enzyme Activation ; Hydrogenase/*metabolism ; Ligands ; Spectroscopy, Fourier Transform Infrared ; Thermotoga maritima/*enzymology
    Published by:
    Latest Papers from Table of Contents or Articles in Press
  2. 2
    KOUSIK, C.S. ; SNOW, J. P. ; BERGGREN, G. T.

    Oxford, UK : Blackwell Publishing Ltd
    Published 1994
    Staff View
    ISSN:
    1365-3059
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes:
    Infection cushions were formed by isolates of Rhizoctonia solani, anastomosis group 1 IA (AG-1 IA, aerial blight) and AG-1 IB (web blight) on leaves of all 10 soybean cultivars tested. Isolates of AG-1 IA and IB did not form infection cushions on soybean leaf surface replicas of either resistant or susceptible cultivars. More infection cushions were formed by isolates of AG-1 IA and IB on collodion membranes placed over leaves of susceptible cultivars compared with resistant cultivars. Isolates of AG-1 IC. AG-4 and AG-5, also formed infection cushions on soybean leaves. However, the isolates of other anastomosis groups did not form infection cushions on soybean leaves. Differential induction of infection cushion formation by the leaves of various plant species was observed, AG-1 IA formed infection cushions on more graminaceous hosts than AG-1 IB, Our results suggest that a chemical stimulus is needed for infection cushion formation. Glucose and 3-O-methylglucose repressed disease severity caused by AG-1 IA and IB isolates to the same extent. Disease severity and the number of infection cushions formed on leaves of ten soybean cultivars were correlated. Fewer infection cushions were formed on resistant cultivars than on susceptible cultivars.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  3. 3
    KOUSIK, C. S. ; SNOW, J. P. ; BERGGREN, G. T. ; HARVILLE, B. G.

    Oxford, UK : Blackwell Publishing Ltd
    Published 1995
    Staff View
    ISSN:
    1365-3059
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes:
    Isolates representing 11 anastomosis groups (AGs) of Rhizoctonia solani from various geographic locations and host plants were tested for virulence on soybean leaves at 15, 20, 25, 30, and 35°C, and on soybean seedlings at 20, 25, and 30°C. Numbers of infection cushions formed on soybean leaves were determined using light microscopy. Isolates of AG-1 IA, AG-1 IB and AG-5 were more virulent on soybean leaves at 20, 25, and 30°C than isolates of AG-1 IC and AG-4. Maximum numbers of infection cushions were formed on soybean leaves by AG-1 (IA, IB, and IC), AG-4, and AG-5 at 25 and 30°C. The other AGs tested did not form infection cushions on soybean leaves although some caused minimal disease severity. Isolates of AG-1 IA formed significantly more infection cushions and caused greater disease severity than AG-1 IB and other isolates at 35°C. Maximum seedling infection, based on per cent area of hypocotyl region covered by lesions occurred at 25 C for AG-1 (IA, IB, and IC) and AG-4. Isolates of AG-5 caused greater seedling infection at 20°C than at 25 and 30°C. The other AGs tested caused only minimal damage to the seedlings. Isolates of AG-4 and AG-5 are not known to cause Rhizoctonia foliar blights of soybean in Louisiana, but their potential to be destructive foliar pathogens is confirmed.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  4. 4
    Kresten, P. ; Berggren, G.

    Amsterdam : Elsevier
    Staff View
    ISSN:
    0040-6031
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Chemistry and Pharmacology
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  5. 5
    Sestak, J. ; Berggren, G.

    Amsterdam : Elsevier
    Staff View
    ISSN:
    0040-6031
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Chemistry and Pharmacology
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  6. 6
    Kresten, P. ; Fels, P. ; Berggren, G.
    Springer
    Published 1975
    Staff View
    ISSN:
    1432-1866
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Geosciences
    Notes:
    Abstract Kimberlitic zircons from 16 intrusions in Lesotho, the Republic of South Africa, and Tanzania have been investigated. The following characteristics distinguish the kimberlitic zircons from the zircons derived from most other sources: 1. Rounded to subrounded grains predominate; euhedral zircons are very rare. 2. Perfect parting in several directions, mainly (100) and (111). 3. Lattice distortions occur (decreasing molar volume). 4. High abundancy of fluid inclusions, occupying healed fractures. 5. Uranium contents less than 30 ppm U. Low contents of Th, Y, P, REE. 6. Whitish alteration rims composed of monoclinic and tetragonal zirconia in varying proportions are common. — The use of zircons in order to identify and trace kimberlite intrusives is discussed, as there may be a possible connection between some properties of the kimberlitic zircons and the diamond grade of their host rocks.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  7. 7
    Berggren, G. ; Christensen, E. Hohwü
    Springer
    Published 1950
    Staff View
    ISSN:
    1439-6327
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Medicine
    Notes:
    Summary The possibility of using heart rate and body temperature as indices of metabolic rate during work has been investigated. Pulse determinations can advantageously be used at work of short duration whereas body temperature determinations can be useful for work of long dunation. These methods have to be used with great care due to the fact that both heart rate and body temperature can vary independent of metabolic rate.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  8. 8
    Berggren, G.
    Springer
    Published 1969
    Staff View
    ISSN:
    1572-8943
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Chemistry and Pharmacology
    Description / Table of Contents:
    Résumé On a étudié par ATD la décomposition de divers carbonates. Les valeurs de l'énergie d'activation et de l'ordre de la réaction ont été calculées d'après les enregistrements d'ATD. Les différentes méthodes utilisées pour ces déterminations ont été comparées. Elles ont donné comme valeur moyenne de l'énergie d'activation 42.3 kcal mol−1 pour CaCO3 et 43.3 kcal mol−1 pour CaC2O4 · H2O. L'étude de la cinétique de la déshydratation de CaC2O4 · H2O par ATD a conduit aux valeurs den=1 et de E=21.7 kcal mol−1. Une seule courbe d'ATD, enregistrée avec une vitesse d'échauffement de 10° min−1, suffit pour évaluer avec entière satisfaction l'énergie d'activation et l'ordre de la réaction. L'exemple de la dolomite illustre l'influence des conditions expérimentales sur le tracé de la courbe d'ATD.
    Abstract:
    Zusammenfassung Die Zersetzung mehrerer Karbonate wurde mittels DTA untersucht. Die DTA-Kurven dienten zur Bestimmung der AktivierungsenergieE und der Reaktionsordnungn. Verschiedene Auswertungsmethoden wurden miteinander verglichen. Die Aktivierungsenergie der Zersetzung von CaCO3 beträgt 42.3 kcal mol−1 als Mittelwert, ausgewertet nach verschiedenen Methoden. Der entsprechende Wert für CaC2O4 · H2O ist 43.3 kcal mol−1. Zusätzlich wurde die Kinetik der Entwässerung von CaC2O4 · H2O mittels DTA untersucht. Die erhaltenen Werte:n=1 undE=21.7 kcal mol−1 stimmen mit Literaturwerten überein. Es wurde gezeigt, daß eine einzige DTA-Aufnahme mit einer Aufheizgeschwindigkeit von 10 °C min−1 eine befriedigende Auswertung der Aktivierungsenergien und Reaktionsordnungen ermöglicht. Der Verlauf der DTA-Kurven bei der Karbonatentsäuerung ist von der Art der Meßköpfe und der Versuchsatmosphäre abhängig. Diese Tatsache wurde am Dolomit unter verschiedenen Versuchsbedingungen bestätigt.
    Notes:
    Abstract The dissociation of several carbonates has been investigated by the DTA method. The curves have been used for the calculation of the activation energy and reaction order. Different evaluation methods have been assessed. The average activation energy for dissociation of CaCO3 is 42.3 kcal mol−1. The corresponding value for CaC2O4 · H2O is 43.3 kcal mol−1. The experimental values for the dehydration of CaC2O4 · H2O,E=21.7 kcal mol−1 andn=1 are in agreement with literature data. It was shown that a single DTA experiment at a heating rate of 10° min−1 is sufficient for the evaluation of the apparent activation energy and reaction order as measured by thermoanalytical methods. The shape of DTA curves is dependent on the experimental conditions as shown by the dissociation of dolomite.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  9. 9
    Berggren, G.
    Springer
    Published 1973
    Staff View
    ISSN:
    1572-8943
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Chemistry and Pharmacology
    Description / Table of Contents:
    Résumé L'exploitation des courbes ATD devrait Être précédée d'une étude approfondie de l'influence des divers types de supports d'échantillon et de cellules, c'est-à-dire d'un examen quantitatif des conditions du transfert de chaleur. L'approximation empirique utilise l'analogie thermique de la loi d'Ohm oùR est la résistance thermique. Le calcul deR donne une correction graphique d'environ 1 mm, ce qui met en relief les mérites du calcul à l'ordinateur. On n'a observé que de très petites différences entre les creusets en platine ou en aluminium contenant les échantillons. On a déterminéR expérimentalement à 500
    Abstract:
    Zusammenfassung Vor der Auswertung von DTA-Kurven sollte eine gründliche Prüfung der verschiedenen Typen von Probebehältern und Zellenblöcken erfolgen, was für die quantitative Abschätzung der Wärmeübertragungsverhältnisse von Bedeutung ist. Die empirische Annäherung macht von dem thermischen Analogen des Ohmschen Gesetzes Gebrauch, wobeiR der thermische Widerstand ist. Die Berechnung vonR ergab eine graphische Korrektion von etwa 1 mm, was die Vorteile der Komputerberechnung betont. Sehr kleine Unterschiede der Werte fürR wurden bei Platin-, bzw. Aluminium-Probebehältern beobachtet.R wurde bei 500
    Notes:
    Abstract Prior to evaluating DTA curves a thorough investigation of different types of specimen holders and cell blocks should be made, which means a quantitative appraisal of heat transfer conditions. The empirical approach makes use of the thermal analogue of Ohm's law, whereR=thermal resistance. Calculation ofR gave a graphical correction of about 1 mm, which stresses the merit of computer calculation. Very small differences of the values forR between platinum and alumina sample holders were observed.R was experimentally determined at 500
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  10. 10
    Kresten, P. ; Berggren, G.
    Springer
    Published 1976
    Staff View
    ISSN:
    1572-8943
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Chemistry and Pharmacology
    Description / Table of Contents:
    Résumé La décomposition endothermique de la thaumasite de Mothae a été étudiée par ATD et TG. Suivant la vitesse de chauffage utilisée la température au sommet du pic varie de 138 à 203° C et l'ordre de réaction de 0.45 à 1.00. On a trouvé que l'énergie d'activation s'élevait à 19 kcal, mol−1 et l'enthalpie à 246 cal. g−1. Il semble que la décomposition s'effectue suivant une réaction d'ordren=0.90, immédiatement suivie par une autre oùn=1.59. On attribue la première réaction à la perte d'eau et la seconde à la libération (partielle) d'hydroxyles OH et d'anhydride carbonique CO2.
    Abstract:
    Zusammenfassung Die durch DTA und TG überprüfte endothermische Zersetzung von Thaumasit aus Mothae zeigt in Abhängigkeit der angewandten Aufheizgeschwindigkeiten Spitzentemperaturen zwischen 138 und 203° C, sowie Reaktionsordnungen von 0.45 bis 1.00. Die Aktivierungsenergie der Reaktion ergab sich zu 19 Kcal/Mol, die Enthalpie zu 246 cal/g. Die Zersetzung scheint in eine Reaktion vonn=0.90 und eine sofort darauffolgende vonn=1.59 geteilt zu sein. Die erste Reaktion wird dem Verlust von H2O, die zweite der (teilweisen) Freisetzung von OH und CO2 zugeschrieben.
    Notes:
    Abstract The endothermic decomposition of thaumasite from Mothae which has been investigated by DTA and TG shows a peak temperature of 138–203°, and reaction orders of 0.45–1.00, depending on the heating rate employed. The activation energy of the reaction was found to be about 19 kcal/mole; the enthalpy is 246 cal/g. The decomposition seems to be divided into one reaction withn=0.90, immediately followed by one withn=1.59. The first reaction is attributed to the loss of H2O, the second one to the (partial) release of OH and CO2.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses