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1.
Commun Biol ; 6(1): 490, 2023 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-37147472

RESUMO

Studies of long-term trends in phenology often rely on climatic averages or accumulated heat, overlooking climate variability. Here we test the hypothesis that unusual weather conditions are critical in driving adult insect phenology. First, we generate phenological estimates for Lepidoptera (moths and butterflies) across the Eastern USA, and over a 70 year period, using natural history collections data. Next, we assemble a set of predictors, including the number of unusually warm and cold days prior to, and during, the adult flight period. We then use phylogenetically informed linear mixed effects models to evaluate effects of unusual weather events, climate context, species traits, and their interactions on flight onset, offset and duration. We find increasing numbers of both warm and cold days were strong effects, dramatically increasing flight duration. This strong effect on duration is likely driven by differential onset and termination dynamics. For flight onset, impact of unusual climate conditions is dependent on climatic context, but for flight cessation, more unusually cold days always lead to later termination particularly for multivoltine species. These results show that understanding phenological responses under global change must account for unusual weather events, especially given they are predicted to increase in frequency and severity.


Assuntos
Borboletas , Mariposas , Animais , Estações do Ano , Tempo (Meteorologia) , Mariposas/fisiologia , Temperatura Baixa
2.
J Med Entomol ; 60(3): 460-469, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-36946466

RESUMO

The adaptation of wildlife species to urban environments can drive changes in the ecology of ectoparasites and vector-borne disease. To better understand ectoparasite dynamics in an urban environment, we investigated the ectoparasite communities of 183 sylvatic and urban opossums and raccoons captured across four seasons at a rural research station and within the city of Gainesville, FL, and of 115 community cats from the Gainesville, FL area. Amblyomma americanum (L.) (Acari: Ixodidae), Dermacentor variabilis (Say), and Ixodes texanus Banks were collected from raccoons, A. americanum, D. variabilis, and Ixodes scapularis Say from opossums, and A. americanum from cats. Few ticks were collected from urban animals, although species richness of ectoparasites was similar between urban and sylvatic habitats. Ctenocephalides felis (Bouché) (Siphonaptera: Pulicidae) was collected from all sampled host species, but was particularly abundant on opossums. Additionally, Orchopeas howardi (Baker) (Siphonaptera: Ceratophyllidae) was collected from raccoons, and O. howardi and Xenopsylla cheopis (Rothschild) (Siphonaptera: Pulicidae) from opossums. Only raccoons were infested with raccoon lice, and only cats were infested with cat lice. Primarily opossums were infested with mites. Ectoparasite community composition varied by habitat, host species, and season; seasonal variation in ectoparasite communities differed between the sylvatic and urban habitats. While urban mesomammals did not appear to play an important role in supporting tick populations in an urban habitat, urban opossums appear to serve as an alternate host for large numbers of cat fleas, which may be an important consideration for treatment and control efforts against ectoparasites of companion animals.


Assuntos
Didelphis , Ixodes , Sifonápteros , Animais , Florida/epidemiologia , Guaxinins/parasitologia
3.
Phys Rev Lett ; 92(5): 054801, 2004 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-14995313

RESUMO

Laser-driven electron accelerators (laser linacs) offer the potential for enabling much more economical and compact devices. However, the development of practical and efficient laser linacs requires accelerating a large ensemble of electrons together ("trapping") while keeping their energy spread small. This has never been realized before for any laser acceleration system. We present here the first demonstration of high-trapping efficiency and narrow energy spread via laser acceleration. Trapping efficiencies of up to 80% and energy spreads down to 0.36% (1 sigma) were demonstrated.

4.
Phys Rev Lett ; 86(18): 4041-3, 2001 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-11328090

RESUMO

Staging of two laser-driven, relativistic electron accelerators has been demonstrated for the first time in a proof-of-principle experiment, whereby two distinct and serial laser accelerators acted on an electron beam in a coherently cumulative manner. Output from a CO2 laser was split into two beams to drive two inverse free electron lasers (IFEL) separated by 2.3 m. The first IFEL served to bunch the electrons into approximately 3 fs microbunches, which were rephased with the laser wave in the second IFEL. This represents a crucial step towards the development of practical laser-driven electron accelerators.

5.
Adolescence ; 20(79): 744-8, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-4083134

RESUMO

The authors completed research on over 700 twelve-year-olds and their parents concerning their attitudes toward the ensuing teenage years. Their responses and written comments reflect and support in large measure the developmental tasks expounded by Robert Havighurst. These include the need to achieve independence, their concern with social relationships, and the acceptance of physical appearance. Parents' concerns about their children becoming teenagers centered on communication and peer pressure.


Assuntos
Adolescente , Atitude , Relações Pais-Filho , Criança , Humanos , Individuação , Ajustamento Social , Conformidade Social
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