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1.
Four distinct forms of native gonadotropin‐releasing hormone (GnRH) and two newly designed analogues were tested for their in vivo activity to induce ovulation in African catfish. The effects of these peptides on ovulatory parameters were compared with those of carp pituitary and [d ‐Ala6, Pro9‐NEt]‐mammalian GnRH analogue (mGnRHa), two tested ovulation‐inducing agents in African catfish. Assessment of ovulation was carried out by determining the ovulation ratio and the relative quantity of egg produced. From the results of the experiments, the order of potency of the native GnRH peptides is summarized as chicken GnRH‐II (cGnRH‐II) >salmon GnRH (sGnRH) >mammalian GnRH >chicken GnRH‐I (cGnRH‐I). Chicken GnRH‐II was as potent as mGnRHa while cGnRH‐I was totally ineffective. The new d ‐Orn6‐cGnRH‐II and d ‐Orn6‐sGnRH with a substitution at position 6 with d ‐isomer residue were as potent as the most extensively used mGnRHa, indicating that the position 6 modification might be more crucial than the substitution at the C‐terminal. On the basis of our results, the potential use and incorporation of cGnRH‐II and sGnRH for the development of more generic spawning induction therapies are suggested. 相似文献
2.
Tomislav Hengl Norair Toomanian Hannes I. Reuter Mohammad J. Malakouti 《Geoderma》2007,140(4):417-427
The paper compares semi-automated interpolation methods to produce soil-class maps from profile observations and by using multiple auxiliary predictors such as terrain parameters, remote sensing indices and similar. The Soil Profile Database of Iran, consisting of 4250 profiles, was used to test different soil-class interpolators. The target variables were soil texture classes and World Reference Base soil groups. The predictors were 6 terrain parameters, 11 MODIS EVI images and 17 physiographic regions (polygon map) of Iran. Four techniques were considered: (a) supervised classification using maximum likelihoods; (b) multinominal logistic regression; (c) regression-kriging on memberships; and (d) classification of taxonomic distances. The predictive capabilities were assessed using a control subset of 30% profiles and the kappa statistics as criterion. Supervised classification and multinominal logistic regression can lead to poor results if soil-classes overlap in the feature space, or if the correlation between the soil-classes and predictors is low. The two other methods have better predictive capabilities, although both are computationally more demanding. For both mapping of texture classes and soil types, the best prediction was achieved using regression-kriging of indicators/memberships (κ = 45%, κ = 54%). In all cases kappa was smaller than 60%, which can be explained by the preferential sampling plan, the poor definition of soil-classes and the high variability of soils. Steps to improve interpolation of soil-class data, by taking into account the fuzziness of classes directly on the field are further discussed. 相似文献
3.
Tzvetan Zlatanov Ivaylo Velichkov Manfred J. Lexer Tomislav Dubravac 《New Forests》2010,40(3):289-303
To study the regeneration dynamics in mature black pine (Pinus nigra Arn.) plantations in the Middle Balkan Range, Bulgaria, a total of 48 research plots (sized 0.1 ha) were established; 26
plots were established in the foothills of the mountains (foothill zone) and 22 in the main massive (mountainous zone). Pine
overstorey as well as advance regeneration in subplots were recorded. Analysis of variance and regression analysis showed
that in general relative stand basal area (RSBA) was the most important predictor of deciduous advance regeneration density,
top height as well as age span of the regeneration layer. In the mountainous zone soil depth (SD) and the presence of mature
deciduous trees (MDT) explained a significant amount of the variation in regeneration features. Lower RSBA induced by earlier
thinnings resulted in higher regeneration density, larger top heights and wider age span of deciduous species. Under the pine
canopy oak regeneration can persist longer compared to natural broadleaved canopies. In the studied plantations pine regeneration
was confined to few scattered seedlings and regeneration groups. Based on these findings silvicultural concepts for the further
management of black pine plantations in the Middle Balkan Range are discussed. 相似文献
4.
Dr. Franz Hengl 《Journal of pest science》1925,1(3):27-28
Ohne Zusammenfassung 相似文献
5.
Ohne Zusammenfassung
Mit 2 Abbildungen 相似文献
6.
Tomislav Tešić 《Plant foods for human nutrition (Dordrecht, Netherlands)》1968,15(4):341-349
Summary Early sowing of winter and spring barley and oats are in general more effective in relation to the attack of frit fly panicle generation than the later sowing, with the exception of late varieties.Meanwhile, we must have in mind that favourable weather conditions in autumn may enable the insects to prolong their activity and to attack the early sowing crops.As well, drought in autumn and low temperature in the spring which occur very often in this area, delay the germination and sprouting so that the heading time of early sown crops coincides with the time of late sown ones.
The paper was presented to the VIth International Congress of Plant Protection, Vienna, 1967. 相似文献
Zusammenfassung Die Fritfliege ist einer der wichtigsten Gersten- und Haferschädlinge in Jugoslawien. Die größten Schäden werden durch die zur Zeit der Rispenbildung auftretende Generation verursacht. Bei Versuchen wurde ermittelt, daß die Ertragseinbuße bei einigen Gerstenvarietäten 80% erreichte.Die chemischen Bekämpfungsmöglichkeiten gegen die Fritfliege sind beschränkt. Indirekte Maßnahmen zur Zeit der Aussaat könnten die Befallsintensität während der Rispenbildung erheblich verringern.Die Befallsintensität steht in direkter Abhängigkeit vom Aussaattermin. Bei früher Aussaat ist die Ertragsminderung viel geringer. Wir empfehlen daher in großen Teilen Jugoslawiens, so früh wie möglich im Frühjahr mit der Aussaat zu beginnen.Die gleiche Empfehlung gilt auch für den Anbau von Wintergerste und -hafer, die vom Befall der Herbstgeneration der Fritfliege und einiger anderer im Frühherbst noch aktiver Schädlinge bedroht sind. Die Möglichkeiten einer frühzeitigen Aussaat in dieser Jahreszeit sind allerdings manchmal durch ungünstige Wetterbedingungen in den betreffenden Gebieten begrenzt.
Résumé En Yougoslavie, l'oscinie (Oscinella frit L.) est l'un des pires parasites de l'orge et de l'avoine. Les plus grands dégâts sont causés par la panicule-génération de cette mouche. Au cours d'expériences, le pourcentage des céréales endommagées atteignait 80 pour certaines variétés d'orge.Les possibilités de lutte chimique contre l'oscinie sont limitées. Des mesures de lutte indirecte au moment des semailles pourraient être d'une grande importance du fait qu'elles réduisent l'intensité d'infestation par la panicule-génération de l'oscinie.L'intensité de l'infestation par la panicule-génération dépend directement de l'époque des semailles. Lorsque les semis sont effectuées de bonne heure, le nombre de grains endommagés est plus bas que lorsque les semis sont faits plus tard. C'est pourquoi l'auteur recommande de procéder dans une grande partie de la Yougoslavie à des semailles de printemps précoces.Il fait les mêmes recommandations pour les semailles d'orge et d'avoine d'hiver. En ce cas, l'auteur étudie l'infestation par la génération de mouches écloses en automne et par d'autres parasites encore atcifs au début de l'automne. Il n'est parfois guère possible de semer de bonne heure à cette saison là, étant donné les conditions atmosphériques défavorables qui règnent dans les régions dont il est question.
The paper was presented to the VIth International Congress of Plant Protection, Vienna, 1967. 相似文献
7.
Grassino Antonela Ninčević Pedisić Sandra Dragović-Uzelac Verica Karlović Sven Ježek Damir Bosiljkov Tomislav 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(3):427-433
Plant Foods for Human Nutrition - In this paper, high-hydrostatic pressure extraction (HHPE) as an emerging food processing and preservation technique constitutes an alternative to conventional... 相似文献
8.
Natalija Filipović Zvonko Stojević Nataša Plevnik Tomislav Mašek Nikica Prvanović Zvonimir Tuček 《Research in veterinary science》2014
The concentrations of carboxyterminal cross-linked telopeptide of type I collagen (CTx), osteocalcin (OCN), parathyroid hormone (PTH) and insulin-like growth factor (IGF-I) were measured in the blood serum of two age groups of mares during late pregnancy (70–50 days before foaling), during early lactation and at the peak of lactation (10–30 and 55–80 days after foaling, respectively). During late pregnancy, the PTH was higher in older (8–19 years old), compared to younger animals (3.5–4 years old) (P < 0.05). The OCN was higher in younger group during late pregnancy (P < 0.05). IGF-I was higher in the younger group during early lactation, in comparison to late pregnancy and the peak of lactation (P < 0.05). IGF-I did not differ between two age groups of mares. The results indicate on the differences in adaptation of bone metabolism to late pregnancy and lactation in older animals, in comparison to younger animals, reflected by elevated PTH secretion. 相似文献
9.
Application of a novel screening procedure, the comparative taste dilution analysis (cTDA), on the non-solvent-extractable reaction products formed in a thermally processed aqueous solution of glucose and l-alanine led to the discovery of the presence of a sweetness-enhancing Maillard reaction product. Isolation, followed by LC-MS and 1D- and 2D-NMR measurements, and synthesis led to its unequivocal identification as N-(1-carboxyethyl)-6-(hydroxymethyl)pyridinium-3-ol inner salt. This so-called alapyridaine, although being tasteless itself, is the first nonvolatile, sweetness-enhancing Maillard reaction product reported in the literature. Depending on the pH value, the detection thresholds of sweet sugars, amino acids, and aspartame, respectively, were found to be significantly decreased when alapyridaine was present; for example, the threshold of glucose decreased by a factor of 16 in an equimolar mixture of glucose and alapyridaine. Studies on the influence of the stereochemistry on taste-enhancing activity revealed that the (+)-(S)-alapyridaine is the physiologically active enantiomer, whereas the (-)-(R)-enantiomer did not affect sweetness perception at all. Thermal processing of aqueous solutions of alapyridaine at 80 degrees C demonstrated a high thermal and hydrolytic stability of that sweetness enhancer; for example, more than 90 or 80% of alapyridaine was recovered when heated for 5 h at pH 7.0, 5.0, or 3.0, respectively. 相似文献