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1.
2.
Response of fourth-instar larvae of Anopheles albimanus Wiedemann (Diptera: Culicidae) to food and inert particles floating at the water surface was studied. In a choice test, larvae aggregated at powdered organic materials (blood meal, liver powder alfalfa flour and wheat flour) but not at inert materials (kaolin, chalk or charcoal). Larvae responded positively to proteins as well as some carbohydrates, but not to cellulose. Retention of larvae at food sources found by random locomotion was found to be responsible for larval aggregation. Larvae ingested food particles 6–9 times faster than insert particles. The significance of Anopheline feeding behavior in the development of formulations of stomach toxins (bacterial agents) used in larval control is discussed.
Zusammenfassung Die vorliegende Studie befasst sich mit Verhaltensreaktionen von Anopheles albimanus Viertlarven auf an der Wasseroberfläche schwimmende Partikel. Verteilung und Orientierung der Larven wurde in einer Wahlapparatur quantifiziert. Nach Auftrag von Alfalfamehl, Weizenmehl, Stärke, Blutmehl, Leberpulver und Fischmehl wurde Aggregation der Larven in den beköderten Fächern der Apparatur beobachtet. Sowohl Proteine (Casein) als auch einige Kohlehydrate (Amylose, Amylopectin) lösten Aggregationen der Larven aus. Im Unterschied dazu führte Auftrag von Kreide, Kaolin, Polyaethylenpulver, Talcum oder Cellulose nicht zu Aggregationen. Zur Beschreibung der Entstehung larvaler Aggregationen bei Futterstoffen wurden die Schwimmbewegungen der Larven in Anwesenheit von Weizenmehl als Ködersubstanz quantifiziert. Da keine Attraktion der Larven im Sinne einer gerichteten Schwimmbewegung beobachtet werden konnte, wird geschlussfolgert, dass sofortige Beendung der Suchaktivität der Larven bei zufällig gefundenen Futterquellen für die beobachteten Aggregationen bei organischen Substanzen verantwortlich ist.Die Fressraten der Larven bei Angebot verschiedener Substanzen im Überschuss wurde bestimmt. Larven fülten drei von insgesamt sechs Darmabschnitten innerhalb von 15–30 min bei Angebot von Futtersubstanzen, während die Füllung von nur zwei Darmabschnitten mit inerten Materialien erst nach 90–120 min zu beobachten war. Die Resultate werden in Bezug auf wasseroberflächengebundene Formulierungen von Frassgiften diskutiert. Inerte Trägersubstanzen werden wahrscheinlich wesentlich langsamer aufgenommen als Futtersubstanzen. Da An. albimanus Larven nicht von Futterquellen angezogen werden, ist eine rasche und wirksame Giftaufnahme besonders dann zu erwarten, wenn die gesamte Oberfläche der Brutgewässer mit toxinhaltigen Trägerpartikeln bedeckt werden kann.相似文献
3.
Influence of prey species and stages on predatory efficiency and development of two phytoseiid mites
The effect of prey species and the different stages of prey on the predatory efficiency and biology of the phytoseiid mites,Amblyseius gossipi
Elbadry andTyphlodromus mangiferus sp. n. was studied. It was found that feeding either predator onTetranychus cucurbitacearum (Sayed) promoted faster development and a higher rate of oviposition than rearing on the twospotted spider mite,T. urticae (Koch). Different stages of both prey species also produced different responses in the biological activities of these predaceous
mites.
Résumé On a étudié l'effet de l'espèce de la proie et de ses différents stades sur l'efficacité et la biologie des acariens phytoseiides,Amblyseius gossipi Elbadry etTyphlodromus mangiferus sp. n. Il a été constaté que l'alimentation des 2 prédateurs avecTetranychus cucurbitacearus (Sayed) assure un dévelopment plus rapide et une fécondité plus élevée que leur élevage surT. urticae (Koch). Les différents stades de ces 2 proies produisent des réponses différentes dans les activités biologiques des 2 acariens prédateurs.相似文献
4.
Nicola Bryson-Morrison Andy Beer Aly Gaspard Soumah Tetsuro Matsuzawa Tatyana Humle 《American journal of primatology》2020,82(3):e23102
Agricultural expansion encroaches on tropical forests and primates in such landscapes frequently incorporate crops into their diet. Understanding the nutritional drivers behind crop-foraging can help inform conservation efforts to improve human-primate coexistence. This study builds on existing knowledge of primate diets in anthropogenic landscapes by estimating the macronutrient content of 24 wild and 11 cultivated foods (90.5% of food intake) consumed by chimpanzees (Pan troglodytes verus) at Bossou, Guinea, West Africa. We also compared the macronutrient composition of Bossou crops to published macronutrient measures of crops from Bulindi, Uganda, East Africa. The composition of wild fruits, leaves, and pith were consistent with previous reports for primate diets. Cultivated fruits were higher in carbohydrates and lower in insoluble fiber than wild fruits, while wild fruits were higher in protein. Macronutrient content of cultivated pith fell within the ranges of consumed wild pith. Oil palm food parts were relatively rich in carbohydrates, protein, lipids, and/or fermentable fiber, adding support for the nutritional importance of the oil palm for West African chimpanzees. We found no differences in the composition of cultivated fruits between Bossou and Bulindi, suggesting that macronutrient content alone does not explain differences in crop selection. Our results build on the current understanding of chimpanzee feeding ecology within forest-agricultural mosaics and provide additional support for the assumption that crops offer primates energetic benefits over wild foods. 相似文献
5.
6.
Iman Y. Zaghloul Mahasen A. Radwan Zinat H. Aly 《Journal of trace elements in medicine and biology》2007,21(2):132-137
Cadmium has been associated with a number of adverse health effects but the impact of those effects on the pharmacokinetics of different drugs has not been investigated. Therefore, the pharmacokinetics of theophylline and ciprofloxacin were studied in cadmium-exposed and control rats (72 rats) following i.p. (6.5mg/kg) and p.o. (10mg/kg) administration, respectively. The third-generation offsprings of rats exposed to 100 microg/mL of cadmium chloride in drinking water were used in this study. Following 8 weeks of exposure, animals received the drugs as a single dose. Blood samples were withdrawn at different time-points and the plasma concentrations of both drugs were analyzed by HPLC. The pharmacokinetic parameters of theophylline and ciprofloxacin were altered significantly in the cadmium-exposed animals. For theophylline, a statistically significant increase (p<0.0001) in C(max) (69%) and AUC(0-)(infinity) (68%) of theophylline in the cadmium-exposed rats as compared to the control were observed. A corresponding significant (p<0.0001) reduction of 41% in clearance (CL/F) of theophylline was detected in the exposed group. Neither the half-life nor the mean residence time (MRT) showed any significant change due to the exposure to cadmium. For ciprofloxacin, no significant difference was seen in the C(max) of the exposed group as compared to the control animals. However, a delay in T(max) was observed in the exposed group (from 0.16(+/-0.003) to 0.37(+/-0.14)h). A small, but significant increase in t(1/2) (p<0.05) was detected (1.74(+/-0.25) vs. 1.45(+/-0.12)h). A significant reduction (p<0.05) of CL/F from 30.54(+/-1.9) to 24.01(+/-3.81)mL/min/kg was seen in the treated group. The current investigation showed that chronic exposure to cadmium could have a very significant impact on altering the pharmacokinetic parameters of various drugs. Therefore, in cadmium-polluted areas, dose adjustments and drug monitoring, especially for drugs with a narrow therapeutic window, should be carried out. 相似文献
7.
Mohamed Aly Radwan Shehata Mohamed Ibrahim Kassem Mahmoud Mohamed Abu-Elamayem Entsar Khalil El-Maadawy 《Archives Of Phytopathology And Plant Protection》2013,46(5):345-352
Abstract The aim of the present study was to formulate six different plant seed oils namely canola, cotton, flax, olive, sesame and soybean as emulsifiable concentrates. The composition of the formulation comprises at least one organic solvent, one surfactant and one plant oil. Physico-chemical properties of the formulated oils (emulsion stability test, cold stability and heat stability tests) were measured. The successfully emulsified oils were evaluated for nematicidal activity against Meloidogyne incognita infecting tomato plants under greenhouse conditions. Emulsified canola oil proved to be the most effective oil as a protectant against M. incognita infection to tomatoes followed by soybean, cotton, flax and sesame oil. In addition, employing a high rate of the tested emulsified oils gave higher activity in suppressing nematodes both in the soil and in tomato roots than using a low rate. Moreover, all tested formulated oils at both rates of application had no adverse effect on the growth of tomato plants except sesame oil which significantly decreased the shoot length when compared to the control. The prepared plant oils might be used as potential sources for sustainable eco-friendly botanical nematicides to protect plants from nematode attack. 相似文献
8.
Amal S. El-Shal Sally M. Shalaby Nader M. Aly Nearmeen M. Rashad Ahmed M. Abdelaziz 《Molecular biology reports》2013,40(11):6063-6073
Obesity, insulin resistance, and hyperandrogenism are considered crucial parameters of polycystic ovary syndrome (PCOS) which might be related to vitamin D metabolism. The aim of this study was to investigate the associations between polymorphisms (TaqI and ApaI) in the vitamin D receptor gene (VDR) and PCOS among Egyptian women. We aimed also to elucidate the impact of these polymorphisms on vitamin D level, hormonal and metabolic parameters of PCOS. One hundred and fifty Egyptian women with PCOS and 150 unrelated controls were enrolled in this study. Polymorphisms of VDR Taq-I T/C (rs731236) and Apa-I A/C (rs7975232) gene were genotyped using polymerase chain reaction restriction fragment length polymorphism (PCR–RFLP). Serum 25 hydroxy vitamin D [25(OH) D] levels were measured by high-performance liquid chromatography. PCOS women had significantly lower levels of 25(OH) D compared to healthy women. Our results revealed that Taq-I CC genotype and C allele were associated with increased risk of PCOS, while the Apa-I polymorphism was not. Haplotype Taq-I C/ Apa-I C was associated with a higher PCOS risk more than controls. Moreover, there was a significant decrease of 25(OH) D levels in carriers of haplotype Taq-I C/ Apa-I C (with variant alleles) compared to the non-carriers. Results showed also that there was an obesity- VDR Taq-I genotypes interactions. These results suggested that, VDR Taq-I gene polymorphism is associated with increased risk of PCOS in Egyptian women. 相似文献
9.
Sonja C. Ludwig Aly McCluskie Paula Keane Catherine Barlow Richard M. Francksen Damian Bubb 《Bird Study》2013,60(4):431-443
Capsule: Diversionary feeding reduced Hen Harrier Circus cyaneus nestlings’ natural food intake by half. Red Grouse Lagopus lagopus scotica chicks constituted 0–4% of all nestling food items. Annually, this reduced annual grouse chick production by 0–6%.Aim: To quantify proportions of diversionary and natural food (including grouse) delivered to Hen Harrier nestlings in relation to brood size, male status and natural prey abundance.Methods: We recorded diversionary food provisioned to 25 Hen Harrier broods (2008–15) and studied the diet of 15 broods using observations from hides, nest cameras and regurgitated pellet analysis. Variation in nestling diet was analysed using compositional analysis.Results: Hen Harriers took 76% of diversionary food provided. Depending on assessment method, average nestling diet was 44–53% diversionary food, 39–55% natural prey (including 24–45% passerines, 4–15% small mammals, 0–4% grouse chicks) and 0–9% unknown items. The amount of diversionary food consumed was not influenced by male status, brood size or natural prey abundance. The number of Red Grouse chicks delivered annually was 34–100% lower than expected under unfed conditions, however, the confidence intervals associated with these estimates were large.Conclusion: Diversionary food influenced Hen Harrier nestling diet and reduced the number of Red Grouse chicks taken relative to modelled predictions. It may help reduce conflict between Hen Harrier conservation and Red Grouse shooting, but only if overall grouse productivity is thereby maintained or increased. 相似文献
10.
Weaam Ebrahim Amal H. Aly Attila Mándi Victor Wray El Mokhtar Essassi Tarik Ouchbani Rachid Bouhfid Wenhan Lin Peter Proksch Tibor Kurtán Abdessamad Debbab 《Chirality》2013,25(4):250-256
Three new polyketides (-)-1 , (+)-1 , and 2 ) were isolated from the EtOAc extract of the fungus Embellisia eureka, an endophyte of the Moroccan plant Cladanthus arabicus (Asteraceae). The structures of these new compounds were determined on the basis of one- and two-dimensional NMR spectroscopy as well as by high-resolution mass spectrometry. The absolute configurations of (-)-1 , (+)-1 , and 2 were determined by TDDFT ECD calculations of solution conformers, online HPLC-ECD analysis, and the modified Mosher method. Chirality 25:250–256, 2013. © 2013 Wiley Periodicals, Inc. 相似文献