Long-term perturbations due to a disturbing body in elliptic inclined orbit

In the current study, a double-averaged analytical model including the action of the perturbing body's inclination is developed to study third-body perturbations. The disturbing function is expanded in the form of Legendre polynomials truncated up to the second-order term, and then is averaged over the periods of the spacecraft and the perturbing body. The efficiency of the double-averaged algorithm is verified with the full elliptic restricted three-body model. Comparisons with the previous study for a lunar satellite perturbed by Earth are presented to measure the effect of the perturbing body's inclination, and illustrate that the lunar obliquity with the value 6.68\degree is important for the mean motion of a lunar satellite. The application to the Mars-Sun system is shown to prove the validity of the double-averaged model. It can be seen that the algorithm is effective to predict the long-term behavior of a high-altitude Martian spacecraft perturbed by Sun. The double-averaged model presented in this paper is also applicable to other celestial systems.Comment: 28 pages, 6 figure

Cognitive Vehicular Networks: An Overview

AbstractCognitive Radio (CR) is extending the applications of wireless communications worldwide. Cognitive radio verifies the electromagnetic spectrum availability and permits the modification of the transmission parameters using the interaction with the environment. The goal is to opportunistically occupy spectral bands with minimum interference to other users or applications. Cognitive radio for Vehicular Ad hoc Networks (CRVs or CR-VANETs) is a new trend in the automotive market. Recent and future vehicles will offer functionalities for the transmission of intra-vehicular commands and dynamic access to wireless services, while the car is in transit. This paper describes the cognitive radio technology and its signal processing perspectives for the automotive market

Queueing systems with different types of renovation mechanism and thresholds as the mathematical models of active queue management mechanism

This article is devoted to some aspects of using the renovation mechanism (different types of renovation are considered, definitions and brief overview are also given) with one or several thresholds as the mathematical models of active queue management mechanisms. The attention is paid to the queuing systems in which a threshold mechanism with renovation is implemented. This mechanism allows to adjust the number of packets in the system by dropping (resetting) them from the queue depending on the ratio of a certain control parameter with specified thresholds at the moment of the end of service on the device (server) (in contrast to standard RED-like algorithms, when a possible drop of a packet occurs at the time of arrivals of next packets in the system). The models with one, two and three thresholds with different types of renovation are under consideration. It is worth noting that the thresholds determine not only from which place in the buffer the packets are dropped, but also to which the reset of packets occurs. For some of the models certain analytical and numerical results are obtained (the references are given), some of them are only under investigation, so only the mathematical model and current results may be considered. Some results of comparing classic RED algorithm with renovation mechanism are presented.Работа посвящена некоторым аспектам использования механизма обновления (различные варианты обновления рассмотрены, определения и краткий обзор представлены) с одним или несколькими порогами в качестве математических моделей механизмов активного управления очередями. Описаны системы массового обслуживания, в которых реализован механизм обновления с порогами, позволяющий управлять числом заявок в системе путем их сброса из накопителя в зависимости от значения некоторого управляющего параметра и пороговых значений. Сброс заявок из накопителя происходит в момент окончания обслуживания заявки на приборе, что отличает данный механизм сброса от RED-подобных алгоритмов, для которых сброс возможен в момент поступления в систему. Представлены модели с одним, двумя или тремя порогами. В этих моделях пороговые значения определяют не только место, с которого в накопителе начинается сброс заявок, но и до какой позиции заявки могут быть сброшены. Для некоторых из описываемых моделей уже получены аналитические и численные результаты (ссылки на работы представлены), но большая часть моделей находится в процессе изучения, поэтому представлены только описания и некоторые текущие данные. Приведены некоторые результаты сравнения классического алгоритма RED с механизмом обновления

Andrological, pathologic, morphometric, and ultrasonographic findings in rams experimentally infected with Brucella ovis

AbstractBrucella ovis is considered the most important infectious cause of reproductive disorders in sheep. The disease is characterized by epididymitis, subfertility and infertility in rams. B. ovis occasionally results in abortion in ewes, as well. The aim of this study was to evaluate kinetic changes in the reproductive organs of rams experimentally infected with B. ovis. Nine rams were experimentally inoculated intrapreputially with 2mL of a suspension containing 1.2×109CFU (colony-forming units)/mL of B. ovis (strain ATCC25840). In addition, 50μL of a suspension containing 1.2×1010CFU/mL of the same B. ovis strain was inoculated into each conjunctival sac, resulting in 3.6×109CFU total per ram. Six of nine infected rams had developed clinical changes in the tail of the epididymis at 30 days post-infection (dpi), but these changes regressed in 50% of these rams. Ultrasound demonstrated an increase in the area of the tail of the epididymis (P<0.001), reduction in the area of the testes (P<0.001), and an increased length and width of the seminal vesicles (P<0.001) during the course of infection. A sperm granuloma was diagnosed on the basis of ultrasonography findings. Microscopically, there was epididymitis, testicular degeneration, and seminal vesiculitis. Inflammatory cells were detected in the semen even before the development of epididymitis. Moreover, inflammatory cells were also found in the semen of asymptomatic rams, indicating that the presence of leukocytes in the ejaculate is a valuable method for screening potential carriers of infections in the genital tract

Behavioral responses of Diaphorina citri to host plant volatiles in multiple-choice olfactometers are affected in interpretable ways by effects of background colors and airflows

[EN] In several phytophagous hemipterans, behavior appears to be mediated by both visual and chemical cues. For the Asian citrus psyllid (ACP)Diaphorina citri(Hemiptera: Liviidae), olfactometric assays are generally difficult to interpret owing to the low proportion of individuals responding to odors (similar to 30-40%), which compromises the efficiency and reliability of the results of behavioral tests. In the present study, the ACP behavioral response to emitted odors from sweet orange (Citrus sinensisL. Osbeck) flushes in a 4-arm olfactometer using different colors (four white-, two white- and two yellow- on opposite sides, or four yellow-colored fields), and the role of the airflow in the concentration of volatile organic compounds (VOCs) were assessed at two airflows [0.4 and 0.1 L/min (LPM)]. Exposure to 'Pera' sweet orange or clean air in treatments with four yellow-colored-fields increased the response rate of ACP females to the odor sources compared with exposure to 'Pera' sweet orange or clean air in treatments with four white-colored-fields, independently of the odor source and airflow tested. For the assays using two white- and two yellow-colored fields on opposite sides and 0.4 or 0.1 LPM airflow, the residence time of ACP females to odors ('Pera' sweet orange or clean air) was similar or higher in treatments using yellow- than those using white-colored fields. For both assays (VOCs and olfactometric behavioral parameters), the reduction in airflow from 0.4 to 0.1 LPM greatly changed the airborne concentration and ACP behavior. Quantitative chemical analyses revelead that the concentration of most compounds emitted by 'Pera' sweet orange flushes for the headspace using 0.1 LPM airflow were greater than the concentrations measured using 0.4 LPM airflow. Therefore, this treatment design provides an useful tool to assess the ACP behavioral response to the odors from citrus plants, and it can also help in the discrimination of dose-response screenings for VOCs or conspecific insects.Financial support was provided by Sao Paulo Research Foundation (FAPESP) 2015/07011-3 and 2017/21460-0. The authors thank Dr. Aquidauana Miqueloto Zanardi for her help in measuring the color spaces of the white and yellow reflective papers used to change the device color.Volpe, H.; Zanardi, O.; Magnani, R.; Luvizotto, R.; Esperança, V.; De Freitas, R.; Delfino, J.... (2020). Behavioral responses of Diaphorina citri to host plant volatiles in multiple-choice olfactometers are affected in interpretable ways by effects of background colors and airflows. PLoS ONE. 15(7):1-17. https://doi.org/10.1371/journal.pone.0235630S117157Grafton-Cardwell, E. E., Stelinski, L. L., & Stansly, P. A. (2013). Biology and Management of Asian Citrus Psyllid, Vector of the Huanglongbing Pathogens. Annual Review of Entomology, 58(1), 413-432. doi:10.1146/annurev-ento-120811-153542Tiwari, S., Mann, R. S., Rogers, M. E., & Stelinski, L. L. (2011). Insecticide resistance in field populations of Asian citrus psyllid in Florida. Pest Management Science, 67(10), 1258-1268. doi:10.1002/ps.2181Zanardi, O. Z., Bordini, G. P., Franco, A. A., de Morais, M. R., & Yamamoto, P. T. (2018). Spraying pyrethroid and neonicotinoid insecticides can induce outbreaks of Panonychus citri (Trombidiformes: Tetranychidae) in citrus groves. Experimental and Applied Acarology, 76(3), 339-354. doi:10.1007/s10493-018-0316-1Stockton, D. G., Martini, X., Patt, J. M., & Stelinski, L. L. (2016). The Influence of Learning on Host Plant Preference in a Significant Phytopathogen Vector, Diaphorina citri. PLOS ONE, 11(3), e0149815. doi:10.1371/journal.pone.0149815Knolhoff, L. M., & Heckel, D. G. (2014). Behavioral Assays for Studies of Host Plant Choice and Adaptation in Herbivorous Insects. Annual Review of Entomology, 59(1), 263-278. doi:10.1146/annurev-ento-011613-161945Döring, T. F., & Chittka, L. (2007). Visual ecology of aphids—a critical review on the role of colours in host finding. Arthropod-Plant Interactions, 1(1), 3-16. doi:10.1007/s11829-006-9000-1NISSINEN, A., KRISTOFFERSEN, L., & ANDERBRANT, O. (2008). Physiological state of female and light intensity affect the host-plant selection of carrot psyllid, Trioza apicalis (Hemiptera: Triozidae). European Journal of Entomology, 105(2), 227-232. doi:10.14411/eje.2008.032MOUND, L. A. (1962). STUDIES ON THE OLFACTION AND COLOUR SENSITIVITY OF BEMISIA TABACI (GENN.) (HOMOPTERA, ALEYRODIDAE). Entomologia Experimentalis et Applicata, 5(2), 99-104. doi:10.1111/j.1570-7458.1962.tb00571.xAntignus, Y., Mor, N., Ben Joseph, R., Lapidot, M., & Cohen, S. (1996). Ultraviolet-Absorbing Plastic Sheets Protect Crops from Insect Pests and from Virus Diseases Vectored by Insects. Environmental Entomology, 25(5), 919-924. doi:10.1093/ee/25.5.919Hall, D. G., Sétamou, M., & Mizell, R. F. (2010). A comparison of sticky traps for monitoring Asian citrus psyllid (Diaphorina citri Kuwayama). Crop Protection, 29(11), 1341-1346. doi:10.1016/j.cropro.2010.06.003Godfrey, K. E., Galindo, C., Patt, J. M., & Luque-Williams, M. (2013). Evaluation of Color and Scent Attractants Used to Trap and Detect Asian Ctirus Psyllid (Hemiptera: Liviidae) in Urban Environments. Florida Entomologist, 96(4), 1406-1416. doi:10.1653/024.096.0420Sétamou, M., Sanchez, A., Saldaña, R. R., Patt, J. M., & Summy, R. (2014). Visual Responses of Adult Asian Citrus Psyllid (Hemiptera: Liviidae) to Colored Sticky Traps on Citrus Trees. Journal of Insect Behavior, 27(4), 540-553. doi:10.1007/s10905-014-9448-2Miranda, M. P., Dos Santos, F. L., Felippe, M. R., Moreno, A., & Fereres, A. (2015). Effect of UV-Blocking Plastic Films on Take-Off and Host Plant Finding Ability of Diaphorina citri (Hemiptera: Liviidae). Journal of Economic Entomology, 108(1), 245-251. doi:10.1093/jee/tou036Paris, T. M., Croxton, S. D., Stansly, P. A., & Allan, S. A. (2015). Temporal response and attraction ofDiaphorina citrito visual stimuli. Entomologia Experimentalis et Applicata, 155(2), 137-147. doi:10.1111/eea.12294Patt, J. M., & Sétamou, M. (2010). Responses of the Asian Citrus Psyllid to Volatiles Emitted by the Flushing Shoots of Its Rutaceous Host Plants. Environmental Entomology, 39(2), 618-624. doi:10.1603/en09216Amorós, M. E., Pereira das Neves, V., Rivas, F., Buenahora, J., Martini, X., Stelinski, L. L., & Rossini, C. (2018). Response of Diaphorina citri (Hemiptera: Liviidae) to volatiles characteristic of preferred citrus hosts. Arthropod-Plant Interactions, 13(3), 367-374. doi:10.1007/s11829-018-9651-8George, J., Shi, Q., Stelinski, L. L., Stover, E., & Lapointe, S. L. (2019). Host Selection, Oviposition and Feeding by a Phytopathogen Vector, Diaphorina citri (Hemiptera: Liviidae), Modulated by Plant Exposure to Formic Acid. Frontiers in Ecology and Evolution, 7. doi:10.3389/fevo.2019.00078Pettersson, J. (1970). An Aphid Sex Attractant. Insect Systematics & Evolution, 1(1), 63-73. doi:10.1163/187631270x00357VET, L. E. M., LENTEREN, J. C. V., HEYMANS, M., & MEELIS, E. (1983). An airflow olfactometer for measuring olfactory responses of hymenopterous parasitoids and other small insects. Physiological Entomology, 8(1), 97-106. doi:10.1111/j.1365-3032.1983.tb00338.xWenninger, E. J., Stelinski, L. L., & Hall, D. G. (2009). Roles of Olfactory Cues, Visual Cues, and Mating Status in Orientation of Diaphorina citri Kuwayama (Hemiptera: Psyllidae) to Four Different Host Plants. Environmental Entomology, 38(1), 225-234. doi:10.1603/022.038.0128Onagbola, E. O., Rouseff, R. L., Smoot, J. M., & Stelinski, L. L. (2010). Guava leaf volatiles and dimethyl disulphide inhibit response of Diaphorina citri Kuwayama to host plant volatiles. Journal of Applied Entomology, 135(6), 404-414. doi:10.1111/j.1439-0418.2010.01565.xAlquézar, B., Volpe, H. X. L., Magnani, R. F., de Miranda, M. P., Santos, M. A., Wulff, N. A., … Peña, L. (2017). β-caryophyllene emitted from a transgenic Arabidopsis or chemical dispenser repels Diaphorina citri, vector of Candidatus Liberibacters. Scientific Reports, 7(1). doi:10.1038/s41598-017-06119-wTomaseto, A. F., Miranda, M. P., Moral, R. A., de Lara, I. A. R., Fereres, A., & Lopes, J. R. S. (2017). Environmental conditions for Diaphorina citri Kuwayama (Hemiptera: Liviidae) take-off. Journal of Applied Entomology, 142(1-2), 104-113. doi:10.1111/jen.12418Wenninger, E. J., & Hall, D. G. (2007). Daily Timing of Mating and Age at Reproductive Maturity in Diaphorina citri (Hemiptera: Psyllidae). Florida Entomologist, 90(4), 715-722. doi:10.1653/0015-4040(2007)90[715:dtomaa]2.0.co;2Shapiro, S. S., & Wilk, M. B. (1965). An Analysis of Variance Test for Normality (Complete Samples). Biometrika, 52(3/4), 591. doi:10.2307/2333709Nelder, J. A., & Wedderburn, R. W. M. (1972). Generalized Linear Models. Journal of the Royal Statistical Society. Series A (General), 135(3), 370. doi:10.2307/2344614Wilcoxon, F. (1945). Individual Comparisons by Ranking Methods. Biometrics Bulletin, 1(6), 80. doi:10.2307/3001968Patt, J. M., Meikle, W. G., Mafra-Neto, A., Sétamou, M., Mangan, R., Yang, C., … Adamczyk, J. J. (2011). Multimodal Cues Drive Host-Plant Assessment in Asian Citrus Psyllid (Diaphorina citri). Environmental Entomology, 40(6), 1494-1502. doi:10.1603/en11149Todd, J. W., Kays, S. J., & Kays, S. E. (1977). A precision low-flow-rate air delivery system for use with olfactometers. Journal of Chemical Ecology, 3(5), 519-525. doi:10.1007/bf00989073Bruce, T. J. A., Wadhams, L. J., & Woodcock, C. M. (2005). Insect host location: a volatile situation. Trends in Plant Science, 10(6), 269-274. doi:10.1016/j.tplants.2005.04.003Bruce, T. J. A., & Pickett, J. A. (2011). Perception of plant volatile blends by herbivorous insects – Finding the right mix. Phytochemistry, 72(13), 1605-1611. doi:10.1016/j.phytochem.2011.04.01

Neoctangium travassosi (Digenea: Microscaphidiidae) in sea turtles from South America

ABSTRACT Sea turtles are endangered animals that present cosmopolitan distribution. Anthropic actions have been considered important causes for the reduction of sea turtle population, but natural aspects such as parasitism may also contribute to their decline. This study aimed to report the occurrence of parasites in stranded dead sea turtles found in an area known as Potiguar Basin, northeastern Brazil, from 2010 to 2019. They were identified and classified according to the carapace length. At post-mortem analyses all organs were examined, parasites collected and morphologically identified. Ecological parasitic indexes as prevalence (P), mean intensity (MI) and mean abundance (MA) were calculated. A total of 80 Chelonia mydas and 5 Eretmochelys imbricata were assessed. Neoctangium travassosi was detected in both species presenting P = 20%, MI = 4.19 and MA = 0.84 for C. mydas and P = 60%, MI = 1.67 and MA = 1.0 for E. imbricata. This is the first report of N. travassosi parasitizing E. imbricata in South America. Finally, the retrieval of these parasites is a warning regarding the need for further studies to assess the impact of this parasitism on the health and conservation of sea turtles