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991.
992.
993.
Timing of larval periods of 9 species of amphibians (Hyla meridionalis, Pelobates cultripes, Discoglossus galganot, Bufo calamita, Bufo bufo, Rana perezi, Triturus marmoratus, Triturus boscat, Pleurodeles waltl) was followed in 7 different years Total larval season may last from autumn to summer, whereas in low rainy years it may last from late winter to summer In rainy years, two species are early breeders, starting to breed m autumn, six species commonly start in mid-winter and one species always breeds later, in spring The widest interannual variability m the onset and duration of larval season occurs in the earliest breeders In general, the more rainy the autumn and the higher temperatures were reached, the earlier the season started In contrast, duration of the season was not correlated with rainfall and temperature Interannual variability is interpreted as the possibility of adjusting the reproduction of the species to the availability of breeding habitats, constrained by physiological features of the species and interspecific relationships  相似文献   
994.
Recent research on mental representation of complex action has revealed distinct differences in the structure of representational frameworks between experts and novices. More recently, research on the development of mental representation structure has elicited functional changes in novices'' representations as a result of practice. However, research investigating if and how mental practice adds to this adaptation process is lacking. In the present study, we examined the influence of mental practice (i.e., motor imagery rehearsal) on both putting performance and the development of one''s representation of the golf putt during early skill acquisition. Novice golfers (N = 52) practiced the task of golf putting under one of four different practice conditions: mental, physical, mental-physical combined, and no practice. Participants were tested prior to and after a practice phase, as well as after a three day retention interval. Mental representation structures of the putt were measured, using the structural dimensional analysis of mental representation. This method provides psychometric data on the distances and groupings of basic action concepts in long-term memory. Additionally, putting accuracy and putting consistency were measured using two-dimensional error scores of each putt. Findings revealed significant performance improvements over the course of practice together with functional adaptations in mental representation structure. Interestingly, after three days of practice, the mental representations of participants who incorporated mental practice into their practice regime displayed representation structures that were more similar to a functional structure than did participants who did not incorporate mental practice. The findings of the present study suggest that mental practice promotes the cognitive adaptation process during motor learning, leading to more elaborate representations than physical practice only.  相似文献   
995.
Commonly applied methods for radiometal-labeling of proteins require complex and protracted derivatization reactions of the protein and the subsequent radiolabeling is time-consuming due to the low reaction temperatures applicable. Therefore, a convenient and efficient prelabeling technique for proteins using the DOTA derivative 2,2′,2′′-(10-(2-(2-mercaptoethylamino)-2-oxoethyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl)triacetic acid (thiol-DOTA) containing a thiol moiety for rapid and selective introduction into maleimide-derivatized proteins was developed. Thiol-DOTA was labeled with 68Ga, 90Y and 177Lu and subsequently introduced into bovine serum albumin and a human IgG with maximum radiochemical yields of 66%. The entire radiolabeling procedure was completed after only 30 min making this a favorable new labeling technique for proteins.  相似文献   
996.
The pollen content of twenty-four unifloral honey samples from twelve different apiaries in La Palma (Canary Islands) was subjected to qualitative and quantitative melissopalynological analysis. The quantitative analysis showed that 4% of the honey belonged to Maurizio's Class I, 8% to Class II, 58% to Class III, 17% to Class IV and 13% to Class V. According to the qualitative analysis, eight honeys were typified as unifloral of Castanea sativa , five of Carlina salicifolia , three of Echium brevirame , three of Reseda luteola , two of Erica arborea , two of Lotus hillebrandii and one of Lamiaceae Origanum vulgare ssp. virens -type. No honeydew elements were found. 62 pollen types were identified belonging to 42 different families. There is no pollen type common to all samples but Foeniculum vulgare -type is present in 22 of the samples (91.7%) and the combination Cistus sp., Erica arborea , Aspalthium bituminosum , Origanum vulgare ssp. virens -type and Rumex sp. in 21 (87.5%). The organoleptic analysis indicated that they are of good quality.  相似文献   
997.
Despite numerous reports on the ability of ascorbic acid and β‐glycerophosphate (AA/β‐GP) to induce osteoblast differentiation, little is known about the molecular mechanisms involved in this phenomenon. In this work, we used a peptide array containing specific consensus sequences (potential substrates) for protein kinases and traditional biochemical techniques to examine the signaling pathways modulated during AA/β‐GP‐induced osteoblast differentiation. The kinomic profile obtained after 7 days of treatment with AA/β‐GP identified 18 kinase substrates with significantly enhanced or reduced phosphorylation. Peptide substrates for Akt, PI3K, PKC, BCR, ABL, PRKG1, PAK1, PAK2, ERK1, ERBB2, and SYK showed a considerable reduction in phosphorylation, whereas enhanced phosphorylation was observed in substrates for CHKB, CHKA, PKA, FAK, ATM, PKA, and VEGFR‐1. These findings confirm the potential usefulness of peptide microarrays for identifying kinases known to be involved in bone development in vivo and in vitro and show that this technique can be used to investigate kinases whose function in osteoblastic differentiation is poorly understood. J. Cell. Biochem. 112: 71–77, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
998.
Summary Results from the operation of methanogenic reactors of three different sizes, using coffee pulp juice as raw material, are presented. All reactors were packed with unreticulated polyurethane foam and geometrical similarity was maintained. Pilot plant operation showed lower gas production per unit reactor volume but higher conversions per unit of organic load, even at lower temperatures.
Resumen Se presentan los resultados de la operación de tres reactores metano-génicos de differente tamaño, usando jugo de pulpa de café como materia prima. Los reactores fueron empacados con esponja de poliuretano no reticulado y se mantuvo una similitud geométrica. La operación de una planta piloto mostró una menor producción de gas por unidad volumétrica de reactor pero conversiones mejores, aún a más bajas temperaturas.

Résumé Les résultats présentés concernant le fonctionnement de trois réacteurs méthanogènes de dimensions différentes, utilisant comme matière première le jus de pulpe de café. Tous les réacteurs étaient compactés avec de la mousse de polyuréthane non réticulée, et avaient des formes géométriques similaires. Les opérations à l'échelle pilote ont donné une moindre production de gaz par unité de volume, mais un taux de conversion par unité de charge organique plus élevé, même à des températures inférieures.


Paper presented at the VII International Conference on the Global Impacts of Applied Microbiology, Helsinki, 12–16 August 1985.  相似文献   
999.
A comparative study of the secondary xylem (wood) anatomy of 11 species (38 specimens) occurring in cerrado s.s. and the adjacent gallery forest (both cerrado s.l. habitat) was made with the aim of identifying the anatomical characteristics of ecological value and correlating them with the environmental conditions. The anatomical features that vary, in general, between the two habitats are: growth ring distinctness (well or poorly defined); tyloses and deposits (more abundant in cerrado specimens); gelatinous fibres (more evident in cerrado specimens and in different patterns between habitats); variation in paratracheal and banded parenchyma (more abundant in cerrado); and more cells per parenchyma strand in cerrado. In general, gallery forest specimens have wider vessels, fewer vessels per square millimetre and larger intervessel pits, indicating more efficient water conduction, whereas cerrado s.s. specimens are the opposite, with low vulnerability and mesomorphy indices, demonstrating greater safety under conditions of water stress. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, ?? , ??–??.  相似文献   
1000.
Many studies have investigated the effect of different parameters of the endodontically restored tooth on its final strength, using in vitro tests and model simulations. However, the differences in the experimental set-up or modelling conditions and the limited number of parameters studied in each case prevent us from obtaining clear conclusions about the relative importance of each parameter. In this study, a validated 3D biomechanical model of the restored tooth was used for an exhaustive sensitivity analysis. The individual influence of 20 different parameters on the mechanical performance of an endodontic restoration with prefabricated posts was studied. The results bring up the remarkable importance of the loading angle on the final restoration strength. Flexural loads are more critical than compressive or tensile loads. Young's modulus of the post and its length and diameter are the most influential parameters for strength, whereas other parameters such as ferrule geometry or core and crown characteristics are less significant.  相似文献   
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