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1.
The daily activity of the slug Arion lusitanicus was studied using time‐lapse video analysis in the laboratory. Under constant temperature (18°C) and 16–h photoperiod, the activity of slugs was measured in half‐hourly periods as locomotor activity, feeding or resting. Track lengths were determined using image analysis. Locomotion of A. lusitanicus was greatest at 5:30, 1.5 h after sunrise, and at 20:30, 1 h after sunset; least locomotor activity occurred between 13:00 and 14:00. The mean distance travelled by A. lusitanicus in 24 h was 10.8 m. The largest slug was the most active and the smallest the least. Slugs spent 68% of 24 hours resting, mainly under artificial shelter traps, 27% in locomotion and 4% feeding. Feeding occurred mainly during the hours of dakness (76%). All categories of behaviour investigated varied greatly between individuals and also between times of day. Homing to artificial shelters and other roost sites was regularly observed within 24 h (41%), but decreased considerably thereafter. The behavioural patterns proved to be in agreement with those found in a previous field investigation and are therefore also discussed with a view to their importance in pest control.  相似文献   
2.
Butterfly migration from and to peninsular Florida   总被引:1,自引:0,他引:1  
Abstract.
  • 1 Migrating butterflies were monitored with traps for 10 years at a site in north peninsular Florida, to determine seasonal and annual variation in numbers and directions of flight.
  • 2 In the spring, 81–96% of the principal migrants, Phoebis sennae (L.), Agraulis vanillae (L.), Precis coenia (Hübner) and Urbanus proteits (L.), flew northward; in the autumn, 86–95% flew southward.
  • 3 Estimated mean net numbers of these four species flying northward in spring across each ENE-WSW metre were 3, 6, 69 and <1 respectively; numbers flying southward in autumn were 222, 413, 37 and 146.
  • 4 During a 5-year period, the ratio of highest to lowest seasonal migration for a species did not exceed 9.3.
  • 5 The average median date of spring migration was 27 March for P.sennae, 23 April for P.coenia, and 12 May for A.vanillae. The average median date of autumn migration was 2–5 October except for U.proteus, whose average date was 14 October.
  • 6 The autumn migratory period, as measured by the duration of the middle half of migration, was about 2 weeks in P.coenia and about 4 weeks in the other three species.
  • 7 Compared to previously reported butterfly migrations, the ones studied here were notably uniform in magnitude and regular in timing.
  • 8 These and other data suggest that 4 million or more of these butterflies migrate northward from peninsular Florida almost every spring and that 40 million or more migrate southward to peninsular Florida almost every autumn.
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3.
A 12 month survey was carried out of the spider population in a commercial citrus grove at Kibbutz Afeq in Northern Israel. The spiders collected from grapefruit foliage and ground cover were identified; young stages were reared to maturity and then identified.Chiracanthium mildei L. Koch represented 52% of all spiders captured during the year andTheridion sp. accounted for 34%. In the undercover,Gnaphosidae spiders represented 43% of the total spiders captured in pitfall traps andLycosidae 35%. A field experiment was carried out to evaluate the effectivness of spiders in biological control of the scaleCeroplastes floridensis Mask. in the citrus ecosystem. Wherever spiders were undisturbed on tree branches, populations ofC. floridensis were not able to develop to a level sufficient to cause economic damage. The increase in the number of scales was minimal: from 47 initially to 56. There was no damage to leaves nor was honeydew or sooty mold observed. During the same time period, on the 3 branches from which spiders had been eliminated, the number of scales increased seven-fold from 44 to 309. Leaves were heavily infested with sooty mold fungi that developed on the honeydew produced by the scales. Contribution from the Agricultural Research Organization, Neve Ya'ar, Regional Experiment Station. P.O. Haifa 31999, Israel. No. 1314-E 1984, series.  相似文献   
4.
The spring dispersal ofSitona lineatus L. (Coleoptera; Curculionidae) was investigated on a Danish farm.S. lineatus dispersed by flight in the early spring on sunny, calm days with temperatures above ca. 15°C. Two thirds of the population ofS. lineatus dispersed from perennial leguminous crops (clover and lucerne) in the first period of flight activity. The next dispersal did not occur until one month later despite several intermediate flight activity periods. The first period of dispersal occurred before the germination of the spring sown summer host crop,Vicia faba L. The field bean crop was infested in three later invasions during a period of more than three weeks. The aggregation pheromone, 4-methyl-3,5-heptanedione, had a significant effect on captures of both males and females in cone traps placed on the ground. There was no effect of the pheromone on captures in yellow sticky traps placed 1.5 m above ground. The pheromone effect is discussed in relation to behavioural observations. Both types of traps may be used in a survey system for monitoring spring dispersal ofS. lineatus and optimal timing of insecticide spraying. However, the pheromone cone traps were highly specific whereas all kinds of flying insects were caught in the yellow sticky traps, thus making the latter traps less suitable for monitoring.  相似文献   
5.
摘要 目的:探究外周血中性粒细胞胞外诱捕网(NETs)、TP53、信号转导与转录因子3(STAT3)表达与弥漫性大B细胞淋巴瘤(DLBCL)临床病理及预后的关系。方法:选取2020年3月-2021年12月收治的71例DLBCL患者作为研究对象,抽取患者外周静脉血,采用R-CHOP方案进行治疗,记录患者外周血NETs、TP53、STAT3表达情况并分析DLBCL患者外周血NETs、TP53、STAT3表达与其临床病理及预后的关系。结果:髓细胞组织增生蛋白(MYC)阳性在TP53阳性中的占比显著高于TP53阴性,差异有统计学意义(x2=28.844,P<0.001);Hans分型生发中心B细胞(GCB)在STAT3阳性中的占比显著高于STAT3阴性(x2=4.331,P=0.037),其余差异无统计学意义(P>0.05);随访截止至2022年6月,随访时长8~28个月,71例患者中共53例缓解DLBCL患者,其余18例为R/R DLBCL患者;NETs阳性、TP53阳性、STAT3阳性患者无进展生存期(PFS)显著低于NETs阴性、TP53阴性、STAT3阴性患者,差异有统计学意义(P<0.05)且NETs阳性、TP53阳性、STAT3阳性患者存活率均低于NETs阴性、TP53阴性、STAT3阴性患者(P<0.05);单因素分析结果显示Ann Arbor分期、NETs、TP53、STAT3为DLBCL患者的影响因素(P<0.05);以患者预后情况(R/R DLBCL=1,缓解DLBCL=0)为因变量,将Ann Arbor分期、NETs、TP53、STAT3单因素分析有统计学意义的因素纳入COX回归模型中,结果显示:NETs、TP53、STAT3为DLBCL患者预后的危险因素(P<0.05)。结论:TP53、STAT3表达与DLBCL临床病理存在一定相关性,临床应对DLBCL患者TP53、STAT3表达情况引起重视;NETs、TP53、STAT3表达为DLBCL预后的危险因素,可作为DLBCL患者不良预后的预测指标。  相似文献   
6.
Abstract 1 Scaphoideus titanus Ball, a nearctic leafhopper introduced into Europe in the 1950s, is known to be the vector of the phytoplasma agent of flavescence dorée (FD), a persistent disease of grapevine. Knowledge of its dispersal patterns is thus very important to prevent disease outbreaks. 2 Yellow sticky traps were used to study the seasonal flight activity of S. titanus, its vertical flight, its movement outside the vineyard and the influence of plant density. Sticky traps of different colours (yellow, red, blue, and white) were also compared. The behaviour of males and females was tested for all those conditions. 3 Abundance was greater in normal than in low plant density conditions, and a positive relationship was found between number of plants per square metre and presence of S. titanus. Leafhoppers did not appear capable of spreading significantly outside a vineyard. Few individuals were trapped above the canopy. Red sticky traps caught more individuals than white, yellow or blue, with the latter showing a poor attractiveness. Sex ratio was almost always male biased. 4 Scaphoideus titanus is monophagous and appears incapable of great dispersal away from its host plant, and females are less likely to fly than males. Further studies on the influence of different factors on the behaviour of this leafhopper are suggested.  相似文献   
7.
Very simply constructed aquatic sticky light traps employing a chemical solution emitting a bright light attracted large numbers of all larval instars, but few pupae of Aedes cantans in trials in England. During April numbers of larvae per trap ranged from 73±14.2 to 163±19.9, whereas dipping with a ladle yielded only 6.9±5.5 to 11.8±7.7 larvae/dip. The traps were also effective in sampling larvae of Culiseta morsitans and in Sierra Leone larvae of Aedes aegypti. It was concluded that sticky light traps could be valuable in sampling relative numbers of mosquito larvae and merited further evaluation.
Résumé Des pièges adhésifs lumineux faciles à réaliser sont construits pour les captures des larves de moustiques. Ils sont formés de paires de boîtes de Pétri en plastique contenant une solution émettrice de lumière provenant de bâtons lumineux chimiques Cyalume®. Chaque piège est recouvert d'une feuille de plastique de 16×16 cm enduite d'une substance qui reste adhésive sous l'eau. Les larves de moustiques attirées vers la source lumineuse viennent se coller à la feuille adhésive.Ces pièges ont été utilisés avec succès en Angleterre pour l'échantillonnage de tous les stades larvaires d'Aedes cantans, mais pas avec le même efficacité pour les nymphes. Des tests plus restreints ont montré que la technique était également utilisable pour les larves de Culiseta morsitans. Les nombres moyens d'A. cantans capturés pendant une piode de 12 h (73±14,2–163±19,9) étaient supérieux à ceux obtenus en plongeant une louche (6,9±5,5–11,8±7,7). En utilisant les pièges adhésifs lumineux, les captures moyennes de C. morsitans étaient également supérieures (12,6±4,7–35,8±8,9) contre (5,7±6,1–8,9±7,8) avec la méthode de la louche.En Sierra Leone, des stades larvaires immatures d'A. aegypti se développant dans des containers de stockage d'eau ont également pu être capturés à l'aide de ces pièges.Bien qu'une évaluation plus poussée soit encore nécessaire, il ne fait aucun doute que ces pièges adhésifs lumineux aient un intérêt considérable pour l'échantillonnage larvaire dans les sites inaccessibles, tels que les trous d'arbres ou les trous de crabes, où les méthodes d'échantillonage classiques sont souvent d'un emploi difficile.
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8.
9.
Tamminga  G. H. 《Hydrobiologia》1992,(1):107-117
In Lake Volkerak, situated in the southwest of the Netherlands, downward settling fluxes are related to external inputs of suspended solids and wind action. The settling fluxes, measured using sediment traps, were 55 g (dw) m –2 d –1 on average. The ratio of metal concentration to scandium concentration was used to discriminate between external (polluted) suspended solids and internal (relatively clean) suspended solids. Generally, the contribution of the river suspended solids was small compared to that of resuspended material; the river-transported material was mainly deposited in the centre and to the east of the lake. The amount of material trapped increased substantially with increasing wind velocity.A simple model was used to interpretate the data. This model does not have a predictive capacity, but can be used to interpret and assess the significance of material retained in the sediment traps. Erosion was related to the wind velocity, using an empirical relationship between the orbital velocity of the wind-generated waves at the bottom and the wind velocity. The critical wind velocity for erosion to occur was estimated to be 5.5 m s–1. The extremely high amounts retained in the sediment traps in shallow areas during storms emphasised the importance of these wind conditions for the transport of fine sediments.  相似文献   
10.
The feasibility of labelling blueberry leaftier by rearing the larvae on blueberry plants treated with foliar sprays of rubidium chloride (RbCl) at concentrations of 1000, 5000, 10 000 and 20 000 ppm were assessed. RbCl sprays above 5000 ppm significantly reduced survivorship to adult stage. The adult longevity, fecundity and mating were not affected when the larvae were reared on foliage treated with 5000 ppm RbCl solution. Reciprocal matings of 5000 ppm treated moths with untreated moths revealed transfer of label above the 0.1 µg Rb/insect threshold level from treated males to untreated females (in 8 out of 13 pairs) and vice versa (in 1 out of 9 pairs). Considerable loss of Rb (56–64%) occurred from the leaves over a 15 day period. All of the moths and pupae collected from the RbCl treated plots in 1989 and 1990 respectively, had a Rb content higher than the threshold level. In a preliminary dispersal study, marked male and female moths were found in sweepnet samples collected 20 and 60 m from the centre of the treated field. Labelled male moths were also captured in pheromone traps arranged in a circle, 40 m from the treated plot.  相似文献   
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