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71.
MÁRCIA FERNANDES DE AQUINO SANTOS JOSÉ RICARDO M. MERMUDES VERA MARIA MEDINA DA FONSECA 《Palaeontology》2011,54(4):807-814
Abstract: A specimen of Curculionidae (Curculioninae) is described as Arariperhinus monnei gen. et sp. nov. The specimen is preserved on a laminated limestone sample of the Crato Formation (Santana Group), Lower Cretaceous (Aptian–Albian), and was collected from a quarry near Nova Olinda, Chapada do Araripe, State of Ceará, Brazil. The genus is placed in the subfamily Curculioninae because of its strongly convex body and relatively slender rostrum, but mainly by its rounded eyes and lack of a prosternal sulcus and tibial spurs. The very prominent eyes in lateral view, a cylindrical rostrum and a straight posterior margin of ventrite II are strong indications that this fossil belongs to the tribe Anthonomini. However, the claws, which would resolve the exact placement of this fossil, are poorly preserved. Arariperhinus monnei gen. et sp. nov. is distinguishable by the combination of several characters and the first record of the family Curculionidae in the Santana Group; it is the oldest record of a member of the subfamily Curculioninae. 相似文献
72.
RICARDO CRUZ DE CARVALHO ANABELA BERNARDES DA SILVA RENATA SOARES ANDRÉ M. ALMEIDA ANA VARELA COELHO JORGE MARQUES DA SILVA CRISTINA BRANQUINHO 《Plant, cell & environment》2014,37(7):1499-1515
All bryophytes evolved desiccation tolerance (DT) mechanisms during the invasion of terrestrial habitats by early land plants. Are these DT mechanisms still present in bryophytes that colonize aquatic habitats? The aquatic bryophyte Fontinalis antipyretica Hedw. was subjected to two drying regimes and alterations in protein profiles and sucrose accumulation during dehydration and rehydration were investigated. Results show that during fast dehydration, there is very little variation in protein profiles, and upon rehydration proteins are leaked. On the other hand, slow dehydration induces changes in both dehydration and rehydration protein profiles, being similar to the protein profiles displayed by the terrestrial bryophytes Physcomitrella patens (Hedw.) Bruch and Schimp. and, to what is comparable with Syntrichia ruralis (Hedw.) F. Weber and D. Mohr. During dehydration there was a reduction in proteins associated with photosynthesis and the cytoskeleton, and an associated accumulation of proteins involved in sugar metabolism and plant defence mechanisms. Upon rehydration, protein accumulation patterns return to control values for both photosynthesis and cytoskeleton whereas proteins associated with sugar metabolism and defence proteins remain high. The current results suggest that bryophytes from different ecological adaptations may share common DT mechanisms. 相似文献
73.
Graham RD Jones Sabrina DA Koetsier 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2014,35(4):243-250
Reference intervals are commonly considered to allow for between-laboratory bias. The RCPAQAP Liquid Serum Chemistry Program has collected data on laboratory measurements as well as reference intervals. This allows assessment of the between-laboratory variation in results, reference intervals and the information transmitted by the combination of these factors. For the majority of common chemistry analytes, the between-laboratory variation in reference intervals is greater than the variation in results. Additionally the reference interval variation is generally not related to bias between the results. Use of common reference intervals, either as an average of the current intervals in use, or the intervals proposed by the AACB Harmonisation Group, improved the variation seen in the information produced by different laboratories. 相似文献
74.
75.
天童常绿阔叶树种栲树生殖个体大小及其生殖构件特征 总被引:9,自引:0,他引:9
对浙江天童木荷-栲树林内的常绿阔叶树种栲树(Castanopsis fargesii Franch.)的生殖个体大小、生殖构件的分布及其动态变化特征进行了研究。结果表明, 该地区栲树生殖个体的胸径在17~50 cm 间, 平均胸径为31. 2±8.0 cm, 平均年龄约36.3±6.6 年;林缘附近的生殖个体小于木荷-林内。相对稳定的群落和比较丰富的土壤养分条件有利于生殖枝数量和花序数量的增多。栲树生殖个体的数量在两年中变化较大, 部分栲树个体可以在连续年份中生殖。从枝系水平分析:在持续生殖的栲树个体上, 生殖枝数量有明显变化, 并非所有的生殖枝在两年中都可开花或结果, 保持连续生殖的枝系约占48.2%。栲树果序枝数量在连续年份有明显差异(p < 0.01), 而且果序枝上的幼蕾数、果实数量及结实率等都有明显差异(p < 0.05)。 相似文献
76.
77.
Indoor and outdoor winter activity of Culicoides biting midges,vectors of bluetongue virus,in Italy 下载免费PDF全文
A. MAGLIANO P. SCARAMOZZINO S. RAVAGNAN F. MONTARSI G. DA ROLD G. CINCINELLI A. MONI P. SILVESTRI A. CARVELLI C. DE LIBERATO 《Medical and veterinary entomology》2018,32(1):70-77
Indoor and outdoor winter activity of Culicoides spp. (Diptera: Ceratopogonidae) in central Italy was investigated in order to evaluate whether indoor activity might account for the overwintering of bluetongue virus, as has been hypothesized by some authors. Weekly Culicoides collections were performed at three farms over three consecutive winter seasons. At each farm, two black‐light traps were operated simultaneously, indoors and outdoors. Culicoides were identified using both morphological and molecular means. The Culicoides obsoletus group accounted for 98.2% of sampled specimens. Within this group, C. obsoletus s.s. accounted for 56.8% and Culicoides scoticus for 43.2% of samples. Nulliparous, parous and engorged females were caught throughout the entire winter, both indoors and outdoors. At times, indoor catch sizes outnumbered outdoor collections. A significant inverse correlation was found between minimum temperature and the proportion of indoor Culicoides of the total midge catch, thus indicating that lower outdoor temperatures drive Culicoides midges indoors. High rates of engorged females were recorded indoors, possibly as the result of the propensity of C. obsoletus females to feed indoors. Higher proportions of parous females were found in indoor than in outdoor catches, indicating higher survival rates indoors and, consequently, higher vectorial capacities of midges sheltering indoors compared with those remaining outdoors. 相似文献
78.
Short-Term In Vitro Culture and Molecular Analysis of the Microsporidian, Enterocytozoon bieneusi 总被引:2,自引:0,他引:2
GOVINDA S. VISVESVARA GORDON J. LEITCH NORMAN J. PIENIAZEK ALEXANDRE J. DA SILVA SARA WALLACE SUSAN B. SLEMENDA RAINER WEBER DAVID A. SCHWARTZ LEO GORELKIN C. MEL WILCOX RALPH T. BRYAN 《The Journal of eukaryotic microbiology》1995,42(5):506-510
ABSTRACT. The microsporidium, Enterocytozoon bieneusi , causes a severe, debilitating, chronic diarrhea in patients with the acquired immunodeficiency syndrome. Specific diagnosis of intestinal microsporidiosis, especially due to Enterocytozoon , is difficult and there is no known therapy that can completely eradicate this parasite. Preliminary studies indicate that a short term (about 6 months) in vitro culture of this parasite yielding low numbers of spores, may be established by inoculating human lung fibroblasts and/or monkey kidney cell cultures with duodenal aspirates and or biopsy from infected patients. The cultures may subsequently be used for the isolation and molecular analysis of parasite DNA. 相似文献
79.
Gram-Chromotrope: a New Technique that Enhances Detection of Microsporidial Spores in Clinical Samples 总被引:3,自引:0,他引:3
HERCULES MOURA JORGE L. NUNES DA SILVA FERNANDO C. SODRÉ PATRICIA BRASIL KRISTY WALLMO SUSANNE WAHLQUIST SARA WALLACE GIAN P. CROPPO GOVINDA S. VISVESVARA 《The Journal of eukaryotic microbiology》1996,43(5):94S-95S
We have developed a new staining procedure that combines the traditional Gram staining for bacteria and the Weber's chromotrope staining method, the standard technique for the detection of microsporidia spores in clinical Specimens. This “Gram-chromotrope” staining technique enhances the staining characteristics of microsporidia spores and facilitates the easy detection and differentiation of spores from other microorganisms that are found in clinical specimens, especially stool samples. This new technique is fast, reliable, and simple to perform, and can be easily adapted for use in clinical laboratories. 相似文献
80.
Transpiration of trees and forest stands: short and long-term monitoring using sapflow methods 总被引:10,自引:0,他引:10
A. GRANIER P. BIRON † N. BRÉDA J.-Y. PONTAILLER ‡ B. SAUGIER‡ 《Global Change Biology》1996,2(3):265-274
We show that sapflow is a useful tool for studies of water fluxes in forest ecosystems, because (i) it gives access to the spatial variability within a forest stand, (ii) it can be used even on steep slopes, and (iii) when combined with eddy correlation measurements over forests, it allows separation of individual tree transpiration from the total water loss of the stand. Moreover, sapflow techniques are quite easy to implement. Four sapflow techniques currently coexist, all based on heat diffusion in the xylem. We found a good agreement between three of these techniques. Most results presented here were obtained using the radial flow meter (Granier 1985). Tree sapflow is computed as sap flux density times sapwood area. To scale up from trees to a stand, measurements have to be made on a representative sample of trees. Thus, a number of trees in each circumference class is selected according to the fraction of sapwood they represent in the total sapwood area of the stand. The variability of sap flux density among trees is usually low (CV. 10–15%) in close stands of temperate coniferous or deciduous forests, but is much higher (35–50%) in a tropical rain forest. It also increases after thinning or during a dry spell. A set of 5–10 sapflow sensors usually provides an accurate estimate of stand transpiration. Transpiration measured on two dense spruce stands in the Vosges mountains (France) and one Scot's pine plantation in the Rhine valley (Germany) showed that maximum rate was related to stand LAI and to local climate. Preliminary results comparing the sapflow of a stand of Pinus banksiana to the transpiration of large branches, as part of the BOREAS programme in Saskachewan, Canada showed a similar trend. For modelling purposes, tree canopy conductance (gc) was calculated from Penman-Monteith equation. In most experiments, calculated canopy conductance was dependent on global radiation (positive effect) and on vapour pressure deficit (negative effect) in the absence of other limiting factors. A comparison of the vapour pressure deficit response curves of gc for several tree species and sites showed only small differences among spruce, oak and pine forests when including understorey. Tropical rainforests exhibited a similar behaviour. 相似文献