Showing papers by "Utrecht University published in 1972"
TL;DR: In this article, a new regularization and renormalization procedure for gauge theories is presented, which is particularly well suited for the treatment of gauge theories and is transparent when anomalies such as the Bell-Jackiw-Adler anomaly may occur.
3,722 citations
TL;DR: The authors found that response latency was inversely related to the retention interval and, although there was more defecation during the 3-h than during the immediate retention test, this could be interpreted as a recency effect rather than as the incubation of fear.
Abstract: Upon leaving an elevated runway to enter a darkened chamber, different groups of rats were given a single electric shock of 0.125, 0.250, or 0.500 mA for 1, 3, or 9 sec. Retention trials, during which latency to enter the darkened chamber and defecation were recorded, were given immediately (30 sec) or 3, 24, or 48 h after the shock trial. Latency and defecation were directly related to both the intensity and duration of the electric shock. No interaction between shock intensity and duration was observed. Response latency was inversely related to the retention interval and, although there was more defecation during the 3-h than during the immediate retention test, this could be interpreted as a recency effect rather than as the incubation of fear.
433 citations
TL;DR: The effect of sterols on the permeability properties of liposomes are in good agreement with the effect on the mean molecular area measured in monolayers, and the effect of these sterol on biological membranes such as erythrocytes and Mycoplasma.
352 citations
TL;DR: In this article, a rigorous combinatorial proof of the independence of the S -matrix of the chosen gauge is presented, which applies to Yang-Mills type theories as well as to gravitation.
347 citations
TL;DR: The unsaturation and the distribution of the double bonds appear to be of critical importance for the barrier properties of lecithins and for the interaction with cholesterol.
320 citations
TL;DR: The results suggest that filipin can interact stoichiometrically with cholesterol and that in membrane systems this interaction is capable of altering some of the physical properties of the membrane, thus providing a basis for Filipin-induced changes in membrane permeability.
283 citations
TL;DR: The effect of incorporated cholesterol and epicholesterol upon the glycerol and erythritol permeability through the membrane of Acholeplasma laidlawii is studied, suggesting the importance of the 3β-OH group of the sterol molecule for the specific sterol-lecithin interaction.
275 citations
TL;DR: The interaction of lecithin and sterol in monolayers is governed by a number of factors including van der Waal's interactions, but also hydrogen bonding between the 3fl-hydroxy group and environment is considered to be important.
261 citations
TL;DR: Fracture faces of the membrane of Acholeplasma laidlawii B below the transition temperature showed structural details that can be attributed to a redistribution of membrane molecules as a consequence of the solidification of the membranes.
209 citations
TL;DR: There was an interrelation between seasonal changes in dry weight and the percentage of glycogen, and the annual glycogen cycle for the total animal consisted of a rapid increase in spring and early summer, followed by small fluctuations in the late summer.
187 citations
TL;DR: In this article, a series of chemically modified lecithins were used to investigate by kinetic analyses their substrate c.q. inhibitor properties for porcine pancreatic phospholipase A.
TL;DR: Measurements by differential scanning calorimetry of the effect of these polyene antibiotics on the phase transition of lecithin and leCithin-cholesterol showed that all polyenes can reduce the ecithin cholesterol interaction.
TL;DR: In this article, Lysine vasopressin with trypsin almost completely destroys the pressor-, antidiuretic-, oxytocic-and corticotrophin-releasing factor activities of lysine vasopharmin, but does not materially influence its effect on the maintenance of an avoidance response.
Abstract: 1. Lysine vasopressin induces resistance to extinction of active avoidance behaviour (De Wied, 1971).
2. Digestion of lysine vasopressin with trypsin almost completely destroys the pressor-, antidiuretic-, oxytocic- and corticotrophin-releasing factor activities of lysine vasopressin, but does not materially influence its effect on the maintenance of an avoidance response.
TL;DR: Treatment with lysine vasopressin increased resistance to extinction, irrespective of the time of treatment, and nonshocked control animals showed no increase in response latencies on successive trials.
Abstract: On a single conditioning trial, a 1-sec electric shock (.125 or.250 mA) was administered when rats entered a darkened chamber from a lighted elevated runway. Latency to enter the chamber was recorded on retention trials given 24 and 48 h later. Animals received subcutaneous injections of varying doses of lysine vasopressin or a placebo solution immediately after the training trial or immediately before the first retention trial. Nonshocked control animals showed no increase in response latencies on successive trials, nor was there a difference between the placebo and vasopressin groups under the “no-shock” condition. Treatment with lysine vasopressin increased resistance to extinction, irrespective of the time of treatment.
TL;DR: Male rats were trained in an active avoidance and/or a “step-through” type of passive avoidance situation and resistance to extinction of active avoidance behavior was obtained when lysine vasopressin was injected 1 hr prior to the first retention trial on Day 3 of training.
TL;DR: The complete amino acid sequence of the basic nuclear protein of bull spermatozoa has been established and the sequence was partially deduced by characterization of peptides isolated from thermolysine and chymotryptic digests of the reduced and S-aminoethylated protein.
TL;DR: In this article, the position of the uv absorption bands of Bi 3+ (1 S 0 3 P 1 transition) and of Eu 3+ in a number of oxides are discussed.
TL;DR: It is concluded from the percentage retention of the tritium label in the main products formed, that these lipoxygenases have opposite stereospecificity in the hydrogen abstraction at carbon n-8: Lipoxygenase from corn germs mainly removes the DR(n-8) hydrogen, whereas lipoxyGENase from soya beans removes the LS(n) hydrogen.
TL;DR: An unsaturated fatty acid requiring auxotroph of Escherichia coli was grown with addition of various uns saturated fatty acids and the permeability of the cells for erythritol appeared to be strongly dependent on the fatty acid incorporated in the membrane lipid.
TL;DR: From the correlation between the permeability properties of cells and liposomes the conclusion is drawn that in S. aureus the chemical nature of the phospholipids determines to a great extent the properties of the permeable barrier.
TL;DR: The results indicate that, in liver, a de novo synthesis is primarily operating in the biosynthesis of linoleic acid-containing molecules of lecithin and of the hexaenoic molecular species of phosphatidylethanolamine and, in lung, an acylation of monoacyl derivatives of these phospholipids is suggested to play an important role particularly in the formation of arachidonic acid containing molecular Species of theseospholipid.
TL;DR: Diphosphatidylglycerol synthesis was found exclusively in the inner mitochondrial membrane and CDP and dCDP diglyceride synthesis occurred primarily in the microsomal fraction.
TL;DR: It is suggested that local anesthetics, particularly when applied in conjunction with pureospholipases, may be useful tools for the detection of the phospholipid arrangement in biological membranes.
TL;DR: Evidence is presented which suggests the operation of the CDP-diglyceride pathway in E. coli at higher concentrations of CDP and phosphatidyl[1'- 14 C]glycerol.
TL;DR: The phospholipid exchange protein from beef liver has been purified 310-fold with an overall recovery of activity of 15 % and was stimulated specifically the exchange of phosphatidylcholine between mitochondria and microsomes.
TL;DR: In an anaerobic system soya-bean lipoxygenase catalyses in the presence of linoleic acid and l-13-hydroperoxyoctadeca-cis-9-trans-11-dienoic acid the formation of dimeric fatty acids and of carbonyl compounds.
Abstract: In an anaerobic system soya-bean lipoxygenase catalyses in the presence of linoleic acid and l-13-hydroperoxyoctadeca-cis-9-trans-11-dienoic acid the formation of dimeric fatty acids and of carbonyl compounds. The analogous reaction does not take place when d-9-hydroperoxyoctadeca-trans-10-cis-12-dienoic acid is used instead of the 13-hydroperoxy isomer. Non-oxygenated dimers stem directly from linoleic acid and have C(11)–C(13′) or –C(9′) and C(13)–C(13′) or –C(9′) linkages. Dimers that contain oxygen originate from linoleic acid and linoleic acid hydroperoxide. It is most likely that the oxygen is present in epoxy groups.
TL;DR: The vibrational spectra of the molecular M6+O6 (M = Mo, Te, W) group in ordered perovskites of the type Ba2M2+M6 +O6 are reported in this article.
TL;DR: In media containing ADP and Mg²+ the longchain acyl-CoA synthetase present in the outer mitochondrial membrane can form linoleyl- CoA, ATP being derived from ADP through the action of adenylate kinase.
TL;DR: Cachexia and depletion of the lymphoid system and liver damage were the most important findings in these animals.
TL;DR: Both the attractiveness of the returned worker and the direction of food exchange indicate that sensory perception by means of the antennae of 9-oxo-decenoic acid on the body of the queen or the substitute queen plays a major part in the "queenright" behaviour of the bees.
Abstract: The material produced in the mandibular glands of queen honey bees can be transported by her attendants and causes an inhibition of oogenesis in the workers who cannot make a direct contact with the queen. It seems that the only substance involved in this procedure is 9-oxo-decenoic acid from the queen's mandibular glands. A worker bee from a queenless group of workers shows a variety of behaviour types when it encounters a queen. This consists of avoidance and aggression, offering food, feeding and retinue behaviour and finally negligence. Although most changes of one behaviour type into another occur randomly, the overall pattern can be divided into an initial phase in which avoidance and aggression are frequently observed, a second phase characterized by feeding and retinue behaviour and a final phase in which negligence of the queen dominates. When back in her group of workers this bee functions as substitute queen by attracting the attention of the others, which show principally the same behaviour types to her. This attractiveness of the substitute queen is due to mandibular gland substances from the queen, adhering to the bee's body. Food exchange between the substitute queen and her attendants is mainly directed to the substitute queen. Feeding by the substitute queen is almost always related to the occurrence of aggression towards her. This is opposite to what might be expected when food exchange would be the mechanism by which information about the presence of the queen is distributed among the colony members. When a queen is deprived of her mandibular glands she evokes the same behaviour types in an encountered bee, but the frequency of negligence is higher, whereas feeding and retinue occur less frequently. When back in her group of workers this bee hardly functions as substitute queen, since she is almost treated as an arbitrary bee. Both the attractiveness of the returned worker and the direction of food exchange indicate that sensory perception by means of the antennae of 9-oxo-decenoic acid on the body of the queen or the substitute queen plays a major part in the "queenright" behaviour of the bees.