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701.
Giovanni Masala 《Journal of forecasting》2013,32(4):369-384
The estimation of hurricane intensity evolution in some tropical and subtropical areas is a challenging problem. Indeed, the prevention and the quantification of possible damage provoked by destructive hurricanes are directly linked to this kind of prevision. For this purpose, hurricane derivatives have been recently issued by the Chicago Mercantile Exchange, based on the so‐called Carvill hurricane index. In our paper, we adopt a parametric homogeneous semi‐Markov approach. This model assumes that the lifespan of a hurricane can be described as a semi‐Markov process and also it allows the more realistic assumption of time event dependence to be taken into consideration. The elapsed time between two consecutive events (waiting time distributions) is modeled through a best‐fitting procedure on empirical data. We then determine the transition probabilities and so‐called crossing states probabilities. We conclude with a Monte Carlo simulation and the model is validated through a large database containing real data coming from HURDAT. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
702.
《Journal of Natural History》2012,46(8):607-639
Although the genus Halecium is easy to recognize, identifications at the species level are often difficult, this even for quite common and supposedly well‐known species of the north‐eastern Atlantic. This paper revises and re‐describes some Halecium species which resemble each other closely and which are not easy to distinguish. Additional information on a few rare species is also provided. The study is based on material collected from the North Atlantic, Mediterranean, South Africa, and New Zealand. Halecium scutum Clark, is recognized as a valid species and distinct from both H. beanii and H. halecinum; colony form and microscopic characters allow a distinction. The pinnate colony form of H. halecinum is a characteristic trait, but not all colonies show this growth form. Halecium beanii can occur in monosiphonic and polysiphonic colonies. Monosiphonic colonies of H. beanii have probably been misidentified by some authors as H. lankesterii. The differences of H. lankesteri to H. beanii and H. petrosum are discussed. The South African population of the reportedly cosmopolitan H. beanii has distinct gonothecae and could belong to a separate species. The Mediterranean Halecium mediterraneum is hardly distinguishable from the New Zealandic H. delicatulum, but it is kept separate mainly for biogeographic reasons. The rare Mediterranean Halecium banyulense is re‐described based on a second find from Naples. The male gonothecae of Halecium corrugatissimum are described for the first time. 相似文献
703.
《Journal of Natural History》2012,46(39):3435-3452
Four new species of Stenothoidae were collected from the Azores Triple Junction zone during different French cruises on the Mid‐Atlantic Ridge. One of the species belongs to the genus Torometopa (T. saldanhae) and is the first record of this genus in the Atlantic Ocean. The three other species belong to the genus Stenothoe (S. divae, S. marvela, and S. menezgweni). It is not possible to determine from morphological and ecological characters whether these amphipod species are endemic to hydrothermal systems or are bathyal species that may be found away from vent sites. 相似文献
704.
《Journal of Natural History》2012,46(48):4081-4099
Three species of scale‐worms inhabiting chaetopterid tubes have been found during routine studies of benthic communities. Anotochaetonoe michelbhaudi gen. and sp. nov. occurred in the East Atlantic off Congo in association with Spiochaetopterus sp. and Phyllochaetopterus sp. It has a relatively short body (fewer than 50 segments); elytra in posterior part of the body arranged on chaetigers 23, 26, 29, 32, 34, 37, 40, 43, 46, present to posterior end; achaetous notopodia; neuropodia long, with longer subtriangular prechaetal lobes and shorter postchaetal lobes rounded distally; upper neurochaetae unidentate and lower bidentate; globular ciliated papillae present between ventral cirri and ventral basis of neuropodia. Lepidasthenia brunnea occurred in the Mediterranean Sea off the French coast both free‐living and in association with Phyllochaetopterus sp. Ophthalmonoe pettiboneae was found in Vietnam (South China Sea) in association with Chaetopterus sp. This is the second finding of the species. The characteristics of the associations between chaetopterid genera and symbiotic polychaetes are discussed. 相似文献
705.
《Journal of Natural History》2012,46(1-2):101-105
Post‐mounting courtship behaviour of a 6–8 mm long scatophagid fly Hydromyza livens which lays its eggs in yellow water lily (Nuphar lutea) is described and analysed. Enigmatic male–male encounters are described, along with lengthy “homosexual” mounting behaviour. A possible interpretation of both types of behaviour is given, with reference to their adaptive significance and the special problems encountered by males in locating females. 相似文献
706.
《Journal of Natural History》2012,46(23-24):1649-1663
The morphology of the tibia and tarsus of all legs is examined in species of two genera of Stephanidae. The subgenual organ (SGO) is examined in more detail for Megischus spp. The fore leg is the most modified in Schlettererius. In Megischus, the SGO of the hind leg is displaced to the middle of the tibia, which is swollen distad of it; in the female the hind tarsi are three‐segmented, the basitarsomere being a composite of tarsomeres 1–3. Internally, the SGO of Megischus is suspended between a spine and a ridge. In the mid and hind legs, part of the tibial wall is thinner in the region of the SGO. Our observations provide circumstantial evidence that female Stephanidae detect substrate‐borne vibrations when searching for hosts. The absence of antennal modification, as well as information on host stage targeted and general behaviour on the oviposition site indicates that they rely on noise made by the host rather than generate vibrations themselves, in contrast to Orussidae, a parasitoid wasp taxon that has been inferred to employ vibrational sounding. The external receptor elements – membranous pads versus tufts of setae – are not homologous in Orussidae and Stephanidae. A spine and ridge suspensorium of the SGO found in members of both families may represent a derived groundplan feature of the orussid–apocritan clade, with secondary modification or reduction in the latter group. Characters of the distal leg elements and the SGO suggest a basal position of Schlettererius and Stephanus within Stephanidae. Modifications of the hind tibia and tarsus in more derived members of the family indicate a shift in relative importance in vibration detection from the fore leg to the hind leg within the family. 相似文献
707.
《Journal of Natural History》2012,46(21-24):1367-1465
The species of the chironomid genus Stempellinella are revised, described, and figured, and keys to known larvae, pupae, and male and female adults are presented. Five species new to science are diagnosed and described. An emended generic diagnosis of Stempellinella is given and morphological differences from its putative sister genus Zavrelia are discussed. The partial cytochrome oxidase subunit I (COI) gene sequences (DNA barcodes) of 10 Stempellinella species are presented and the variation in genetic distances within and between species is compared. The results indicate that DNA barcodes are suitable molecular markers for identification of Stempellinella species. The following life stages and species are diagnosed and described: the larva, pupa, male, and female of S. brevis, S. chambiensis, S. ciliaris, S. edwardsi, S. fimbriata sp. n., S. flavidula, S. leptocelloides, S. saltuum, and S. truncata; the pupa, male, and female of S. reissi and S. tamaseptima; the larva, pupa, and male of Stempellinella boltoni sp. n.; the pupa and male of S. lamellata sp. n.; the male and female of S. coronata; and the male of S. apicula, S. brevilamellae, S. distincta sp. n., and S. sublettorum sp. n. Two pupal types are described but not formally named. The following changes of combination are made: Stempellina chambiensis and Stempellina truncata are transferred to the genus Stempellinella. Zavrelia inopinata is listed as a new junior synonym of Stempellinella ciliaris. 相似文献
708.
《Journal of Natural History》2012,46(43-44):2793-2807
There are multiple factors that may determine individual and population growth rates and understanding the impact of extrinsic factors, such as temperature, is important for successful recovery plan stock assessment and modelling. In January 2001 and January 2003, cold‐stunning events occurred along the northern Gulf of Mexico, in St Joseph Bay, Florida. In this study we examine the short‐term effects of decreased water temperatures and repeated cold‐stunning events on the growth of juvenile green turtles in northwest Florida. There were no significant effects of number of cold‐stunning events on growth, although turtles stunned twice tended to grow slower than non‐stunned turtles. This is the first study to provide information on the growth rates of green turtles in the northern Gulf of Mexico and it is the first examination of the effects of cold‐stunning on growth in any sea turtle population. 相似文献
709.
Eugene Kouassi Joel Sango J. M. Bosson Brou Francis N. Teubissi Kern O. Kymn 《Journal of forecasting》2011,30(6):541-564
In this paper we extend the Baillie and Baltagi ( 1999 ) paper (Prediction from the regression model with one‐way error components. In Analysis of Panels and Limited Dependent Variables Models, Hsiao C, Lahiri K, Lee LF, Pesaran H (eds). Cambridge University Press, Cambridge, UK). In particular, we derive six predictors for the two‐way error components model, as well as their associated asymptotic mean squared error (AMSE) of multi‐step prediction. In addition, we also provide both theoretical and simulation evidence as to the relative efficiency of our six alternative predictors. The adequacy of the prediction AMSE formula is also investigated by the use of Monte Carlo methods which indicate that the ordinary optimal predictors perform well for various accuracy criteria. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
710.
This paper proposes a strategy to detect the presence of common serial cor‐ relation in large‐dimensional systems. We show that partial least squares can be used to consistently recover the common autocorrelation space. Moreover, a Monte Carlo study reveals that univariate autocorrelation tests on the factors obtained by partial least squares outperform traditional tests based on canonical correlation analysis. Some empirical applications are presented to illustrate concepts and methods. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献