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1.
Nonlinear component of variance models   总被引:1,自引:0,他引:1  
SOLOMON  P. J.; COX  D. R. 《Biometrika》1992,79(1):1-11
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2.
Summary Urticaceae pollen monitoring was carried out, in the atmosphere of East Perugia during the summer of 1989. In summer the Urticaceae pollen shows a fluctuating diurnal trend, which was analysed daily over six 4-hour periods. The high peaks of thistaxon were recorded in the middle of the day in July and August, and in the morning in June. The percentage pattern of the daily mean pollen concentration of Urticaceae was compared with mean temperature, wind speed, relative humidity and rain, both in the non-rainy days and rainy ones. The best correlations came out comparing pollen concentration and meteoclimatic parameters during non-rainy days. The interpretation of the influence of rainfalls is very difficult owing to their peculiar features in summer.  相似文献   

3.
Summary From May 1986 to May 1989 surveys of airborne biological particles have been performed in the atmosphere of Cosenza, Italy with the aim of monitoring the presence of airborne pollen. The survey station is situated at Arcavacata of Rende, a hilly area 474 meters above sea level, 7 km north-west of the main town. The sampler (VPPS 2000) is located about 20 meters above ground level. The monitoring, performed in accordance with the criteria suggested by the Italian Association of Aerobiology (A.I.A.), enabled the identification of 26 different pollen types. The pollination graphics show: 1) a late winter period in which pollen from trees appears; 2) a spring period with a prevalence of Gramineae, Fagaceae, Oleaceae andParietaria pollen; 3) a late spring-summer period during which Fagaceae,Pinus and Compositae pollen grains are present; 4) a late summer-autumn and winter period characterized by a drastic reduction of airborne pollen. A study of the calendar reveals, furthermore, that: 1) Gramineae pollen is, amongst those of allergological importance, the most representative; 2)Parietaria is not perennial and is present in modest concentrations; 3)Olea reaches a high peak in June, but not as high as in other southern regions; 3) pollen from arboreal plants is prevalent compared to that of herbaceous plants.  相似文献   

4.
Summary The aim of this study is the evaluation of clinical significance of the allergic sensitization toOlea europaea L. pollen allergens in the Naples area, because in the last 10 years an increasing frequency of IgE mediated sensitization to these allergens has been observed. 4124 patients of both sexes (2989 adults and 1153 children) consecutively examined in our Allergological Center from January 1, 1988 to December 30, 1989 have been considered in this study. The patients were selected on the basis of a history of rhinitis (R) and/or asthma (A) and were evaluated by clinical examination, SPT, RAST and specific or aspecific BPT. Among 2267 adults and 879 children sensitized to almost one aeroallergen we found respectively 306 (13.49%) and 75 (8.53%) subjects with an allergic sensitization toOlea europaea L. pollen. The frequency of clinical manifestation was respectively R+A (58.16%), R (39.54%), A (2.28%) in adults; R+A (61.33%), R (26.66%), A (12%) in children. A monosensitization toOlea europaea L. pollen was found in 1.33% of children and in 2.28% of adults examined. The association with other allergens especially with mites and/or other pollen was very common.  相似文献   

5.
The behaviour of Celtis airborne pollenwas studied for a period of three years(1998–2000) in the city of La Plata. The pollengrains were captured with a Lanzoni trap andthe maximum pollination period was observed tooccur during the end of winter and spring inthe three years. The annual values of pollenconcentration varied, and a significantdecrease was observed during 2000. The greatestairborne pollen record was in October with anaverage of 82.3% in relation to its totalconcentration during 1998–2000. Based on theintradiurnal behaviour analysis, it wasobserved that the maximum pollination peakoccurs at 2H when the temperaturereaches its maximum values. Considering thethree sampling years, the meteorologicalvariables that most influenced the processes of pollen emission,dispersion and transportation in the atmospherewere: maximum and minimum temperature andrainfall.  相似文献   

6.
Summary A comparative study was carried out between aeroallergenic pollen spectra in Trieste and at Lozzo di Cadore. The two localities were found to be different on a five-day running mean basis as to the 8 pollen taxa monitored by the National Aerobiological Monitoring Network managed by the Italian Association of Aerobiology (AIA). In the zone of Lozzo the pollination curve of the spring flowering taxa showed a lag of about one month due to the colder climate. Lozzo di Cadore showed a poor airborne pollen content,Corylus and Graminaceae being prevailing. Trieste has a higher airborne pollen diversity and longer pollination times because of its higher floristic and vegetational complexity. In Trieste the allergenic pollen spectrum showed great quantities ofOstrya, Quercus, Oleaceae, Graminaceae and of ruderal taxa, widespread over the area, due to man's influence.  相似文献   

7.
Understanding daily stem size variation is important as the net increment of a forest stand is ultimately determined by the accumulation of daily increment events. In this study, measurements of stem size at high spatial and temporal resolution were made using two commercial hybrid Eucalyptus clones [E. grandis × urophylla (GU) and E. grandis × camaldulensis (GC)] over a period of more than 3.5 years in order to better understand how daily stem growth is effected by variations in environmental conditions. It was evident that GU had fewer days on which net growth occurred than GC. However, when growth did occur, GU grew for longer each day and at a higher rate than GC. Thus, it still had an overall larger net stem increment during the study period. The GU clone had a markedly intermittent pattern of growth, such that growth essentially ceased under drought conditions, but responded rapidly when water became available. This confirms other findings that E. grandis × urophylla is more susceptible to drought stress than E. grandis × camaldulensis, but emphasizes that a strategy of “rapid response” when environmental conditions become temporarily non-limiting is a good one in terms of net increment at sites such as in this study.
David Michael DrewEmail:
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8.
Summary This contribution presents a procedure for estimating the distribution of pollen sources and mapping their activity. Particular reference is made to the example of mapping the pollen emissions ofCastanea sativa, in the Reno valley near Bologna (Italy), achieved with numerical techniques and starting from basic maps (vegetation, topographic and pedologic), phenological observations and pollen production data.  相似文献   

9.

Background

Dominance effect may play an important role in genetic variation of complex traits. Full featured and easy-to-use computing tools for genomic prediction and variance component estimation of additive and dominance effects using genome-wide single nucleotide polymorphism (SNP) markers are necessary to understand dominance contribution to a complex trait and to utilize dominance for selecting individuals with favorable genetic potential.

Results

The GVCBLUP package is a shared memory parallel computing tool for genomic prediction and variance component estimation of additive and dominance effects using genome-wide SNP markers. This package currently has three main programs (GREML_CE, GREML_QM, and GCORRMX) and a graphical user interface (GUI) that integrates the three main programs with an existing program for the graphical viewing of SNP additive and dominance effects (GVCeasy). The GREML_CE and GREML_QM programs offer complementary computing advantages with identical results for genomic prediction of breeding values, dominance deviations and genotypic values, and for genomic estimation of additive and dominance variances and heritabilities using a combination of expectation-maximization (EM) algorithm and average information restricted maximum likelihood (AI-REML) algorithm. GREML_CE is designed for large numbers of SNP markers and GREML_QM for large numbers of individuals. Test results showed that GREML_CE could analyze 50,000 individuals with 400 K SNP markers and GREML_QM could analyze 100,000 individuals with 50K SNP markers. GCORRMX calculates genomic additive and dominance relationship matrices using SNP markers. GVCeasy is the GUI for GVCBLUP integrated with an existing software tool for the graphical viewing of SNP effects and a function for editing the parameter files for the three main programs.

Conclusion

The GVCBLUP package is a powerful and versatile computing tool for assessing the type and magnitude of genetic effects affecting a phenotype by estimating whole-genome additive and dominance heritabilities, for genomic prediction of breeding values, dominance deviations and genotypic values, for calculating genomic relationships, and for research and education in genomic prediction and estimation.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2105-15-270) contains supplementary material, which is available to authorized users.  相似文献   

10.
A simple receptor modeling approach has been applied to groundwater pollution studies and has shown that maker trace elements can be used effectively in source identification and apportionment. Groundwater and source materials from one coal-fired and five oil-fired power plants, and one coal-tar deposit site have been analyzed by instrumental neutron activation analysis for more than 20 minor and trace elements. In one of the oil-fired power plants, trace element patterns indicated a leak from the hazardous waste surface impoundments owing to the failure of a hypolon liner. Also, the extent and spatial distribution of groundwater contamination have been determined in a coal-tar deposit site.  相似文献   

11.
Palaeoecological data are compared with output from climate-driven forest simulation models to separate human influence as a driver of vegetation dynamics from other drivers such as climatic change. The transition from Tilia cordata to Fagus sylvatica dominance in a small forest hollow in Denmark was not predicted by a climate-driven forest simulation model and could be ascribed to anthropogenic impact. This transition can be upscaled to a large region of north-west Europe and contributes to a data-model mismatch for the European distribution of Fagus 6,000 years ago. A data-model mismatch for Picea abies during the last few centuries in southern Scandinavia can also be attributed to anthropogenic impact. Combining pollen data and vegetation models can help with the important task of upscaling from the scale of the forest stand, where anthropogenic impact is readily detectable, to regions and continents, where it is more challenging to distinguish anthropogenic impact from the impacts of climatic change.  相似文献   

12.
Ambrosia sp. pollen in Switzerland   总被引:1,自引:0,他引:1  
The presence of Ambrosia sp. pollen is very irregular inSwitzerland. South to the Alps (Ticino), the yearly meanquantities (1993 to 1997) reach 535 pollen grains in Lugano and114 in Locarno. To the West, 205 pollen grains of Ambrosiasp. are observed as yearly mean total in Geneva. In La Chaux-de-Fonds(100 a.s.l.), a yearly mean of 86 pollen is reached, 66 inNeuchâatel, 59 in Payerne and 74 in Basel. In the Swiss RhoneValley, in Visp, this yearly mean reaches 30 pollen ofAmbrosia sp. A little more in the center of the country, inBern, 31 pollen are monitored as yearly mean quantity. In therest of the helvetic territory, in the North and in the East, theyearly mean are below 15 pollen grains. Since 1991–1992, anincrease has been observed essentially in Ticino, in Geneva,Neuchâatel and La Chaux-de-Fonds. The presence of Ambrosiasp. pollen is often noticed in case of strong west or south-westwind flowing, probably coming from the Rhôone Valley and theBresse in France and the Po Valley in Italy.  相似文献   

13.
Laboratory experiments compared the nutritive value of various pollen sources for the development of Coleomegilla maculata DeGeer under conditions of continuous water availability and simulated drought. When water was continuously available, larval survival was not different from 100% on diets of frozen eggs of Ephestia kuehniella Zeller, corn pollen, sorghum pollen, or pulverized bee pollen, whereas survival of larvae was significantly reduced on the latter three diets in the simulated drought treatment. Pollen of cultivated sunflower, Helianthus annus L., proved fatal to both larvae and adults; its surface structure caused clumping and accumulation on the insect cuticle that led to death from exhaustion/desiccation in petri dishes. The Ephestia egg diet yielded shorter developmental times and heavier adult weights than any pollen diet in both treatments. The drought treatment increased developmental time on all diets with a significant treatment–diet interaction. Drought reduced the adult weight of females on the sorghum pollen diet, and that of both sexes on the bee pollen diet, again with a significant treatment–diet interaction. Initial water content was highest in corn pollen (36.8%), followed by Ephestia eggs (29.2%), sorghum pollen (25.3%), sunflower pollen (8.7%), and bee pollen (4.6%), but did not appear correlated with C. maculata larval survival on pollen sources under drought conditions. Reproductive adult females that received corn or sorghum pollen as a supplement to Ephestia eggs did not differ in fecundity or fertility from those fed only Ephestia eggs.  相似文献   

14.
Betula pollen is a common cause of pollinosis in localities in NW Spain and between 13% and 60% of individuals who are immunosensitive to pollen grains respond positively to its allergens. It is important in the case of all such people to be able to predict pollen concentrations in advance. We therefore undertook an aerobiological study in the city of Vigo (Pontevedra, Spain) from 1995 to 2001, using a Hirst active-impact pollen trap (VPPS 2000) situated in the city centre. Vigo presents a temperate maritime climate with a mean annual temperature of 14.9 °C and 1,412 mm annual total precipitation. This paper analyses two ways of quantifying the prediction of pollen concentration: first by means of a generalized additive regression model with the object of predicting whether the series of interest exceeds a certain threshold; second using a partially linear model to obtain specific prediction values for pollen grains. Both models use a self-explicative part and another formed by exogenous meteorological factors. The models were tested with data from 2001 (year in which the total precipitation registered was almost twice the climatological average overall during the flowering period), which were not used in formulating the models. A highly satisfactory classification and good forecasting results were achieved with the first and second approaches respectively. The estimated line taking into account temperature and a calm S–SW wind, corresponds to the real line recorded during 2001, which gives us an idea of the proposed models validity.  相似文献   

15.
Summary Pollen-collecting bumble bees (Bombus spp.) detect differences between individual flowers in pollen availability and alter their behavior to capitalize on rewarding flowers. Specific responses by bees to increased pollen availability included: longer visits to flowers; visits to more flowers within an inflorescence, including an increased frequency of revisits; an increased likelihood of grooming while the bee flow between flowers within the inflorescence; and more protracted inter-flower flights, probably because of longer grooming bouts. The particular suite of responses that a bee adopted depended on the pollen-dispensing mechanism of the plant species involved. Bees buzzed previously-unvisited Dode-catheon flowers longer than empty flowers. In contrast, pollen availability did not significantly affect the duration of visits to Lupinus flowers, which control the amount of pollen that can be removed during a single visit. Simulation results indicate that the observed movement patterns of bumble bees on Lupinus inflorescences would return the most pollen per unit of expended energy. The increased foraging efficiency resulting from facultative responses by bees to variation in pollen availability, especially changes in the frequency and intensity of grooming, could correspondingly decrease pollen dispersal between plants.  相似文献   

16.
In the present paper are summarized our results on obtaining tobacco male sterile forms through interspecific hybridization. The wild species Nicotiana velutina, N. benthamiana, N. maritima, N. paniculata were used as cytoplasm donors and N. tabacum as the donor of the nucleus. Completely sterile hybrids from these combinations were obtained whose sterility was overcome through the use of tissue culture. Stem parenchyma grown in vitro on MS medium was used for inducing callus, and for organogenesis and rooting. The regenerants obtained were mixoploid. Male sterile plants were obtained in BC1P2 progenies from the combinations between N. velutina × N. tabacum, N. benthamiana × N. tabacum and in R2 progenies from N. maritima × N. tabacum and N. paniculata × N. tabacum. The observed male sterility was preserved in BC1P2-BC7P2 progenies and was identified as cytoplasmic male sterility (CMS) because it was inherited only throuth the female parent.  相似文献   

17.
Summary A factorial cross design was used to evaluate the influence of differences among pollen donors and recipients on variation in stylar attrition of pollen tubes in self-fertile plants of Petunia hybrida. Pollinations to flower buds were used to reduce the inhibitory ability of the style and these crosses were compared with flower pollinations to assess the degree of stylar influence on pollen fertilization ability. There was less pollen tube attrition after bud pollinations than after flower pollinations, indicating that styles of buds were less able to inhibit pollen tubes. The variance component for plants acting as pollen donors tended to be greater after flower pollinations than after bud pollinations. The lower variance in male success after bud pollinations indicates that differences among pollen donors after flower pollinations were due to stylar inhibition of pollen rather than differences in pollen vigor. Since the level of variation in pollen growth after pollination to flowers was greater among clones than among ramets within clones, the differences in pollen fertilization ability are probably genetically based.  相似文献   

18.
Developing jellyfish strategy hypotheses using circulation models   总被引:2,自引:0,他引:2  
Four species of ergasilid copepods were collected from gill filaments of three species of fishes from Khor al-Zubair Lagoon, Iraq. The mugilid Liza subviridis hosted the new species Ergasilus iraquensis and Ergasilus pararostralis. Ergasilus synanceienis sp. n. was found on the synanceiid Leptosynanceia melanostigma(Day). The fourth species, Dermoergasilus varicoleus Ho, Jayarajan & Radhakrishnan, 1992 was found parasitizing the mugilid Liza abu, and is a new record for Iraq.  相似文献   

19.
The present paper describes the comparative biochemical studies in terms of quantitative analyses of carbohydrates, lipids, proteins, free amino acids, nucleic acids, minerals, ash and moisture as well as the identification of free amino acids of pollen of four species ofCassia L. (C. alata L,C. fistula L,C. occidentalis L andC. siamea Lam.). A significant variation in the chemical constituents was observed among the four species.C. occidentalis showed the highest levels of carbohydrate (15.15%) and protein (22.45%), andC. siamea had the lowest levels of carbohydrate (7.15%), lipid (6.2%) and protein (13.85%).C. alata andC. fistula showed intermediate results. However,C. alata showed the highest amount of free amino acids (3.8%) and the least of 1.42% was found inC. fistula. Thin layer chromatography (TLC) of free amino acids of the four species showed some homology in their amino acid content, of which proline, glutamic acid, methionine and phenyl-alanine were the most dominant. The level of nucleic acids and minerals was found to be comparatively low.C. siamea andC. alata showed an exceptionally high level of ash content (8.6 and 8.8%, respectively) while moisture content varied from 8 to 11%.  相似文献   

20.
Gilboa S  Nonacs P 《Oecologia》2006,146(4):667-674
Parental investment strategies can be fixed or flexible. A fixed strategy predicts making all offspring a single ‘optimal’ size. Dynamic models predict flexible strategies with more than one optimal size of offspring. Patterns in the distribution of offspring sizes may thus reveal the investment strategy. Static strategies should produce normal distributions. Dynamic strategies should often result in non-normal distributions. Furthermore, variance in morphological traits should be positively correlated with the length of developmental time the traits are exposed to environmental influences. Finally, the type of deviation from normality (i.e., skewed left or right, or platykurtic) should be correlated with the average offspring size. To test the latter prediction, we used simulations to detect significant departures from normality and categorize distribution types. Data from three species of ants strongly support the predicted patterns for dynamic parental investment. Offspring size distributions are often significantly non-normal. Traits fixed earlier in development, such as head width, are less variable than final body weight. The type of distribution observed correlates with mean female dry weight. The overall support for a dynamic parental investment model has implications for life history theory. Predicted conflicts over parental effort, sex investment ratios, and reproductive skew in cooperative breeders follow from assumptions of static parental investment strategies and omnipresent resource limitations. By contrast, with flexible investment strategies such conflicts can be either absent or maladaptive. Electronic Supplementary Material Supplementary material is available for this article at  相似文献   

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