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461.
Predation on arboreal mammals is rarely observed in the wild. Here we describe the first confirmed observations of predation
on a juvenile wild common marmoset (Callithrix jacchus) and on a neonate wild pale-throated three-toed sloth (Bradypus tridactylus) by the mustelid carnivore Eira barbara, the tayra. We discuss predation on both of the prey species and review the nature of predation by the tayra. 相似文献
462.
463.
Industrial biotechnology employs the controlled use of microorganisms for the production of synthetic chemicals or simple
biomass that can further be used in a diverse array of applications that span the pharmaceutical, chemical and nutraceutical
industries. Recent advances in metagenomics and in the incorporation of entire biosynthetic pathways into Saccharomyces cerevisiae have greatly expanded both the fitness and the repertoire of biochemicals that can be synthesized from this popular microorganism.
Further, the availability of the S. cerevisiae entire genome sequence allows the application of systems biology approaches for improving its enormous biosynthetic potential.
In this review, we will describe some of the efforts on using S. cerevisiae as a cell factory for the biosynthesis of high-value natural products that belong to the families of isoprenoids, flavonoids
and long chain polyunsaturated fatty acids. As natural products are increasingly becoming the center of attention of the pharmaceutical
and nutraceutical industries, the use of S. cerevisiae for their production is only expected to expand in the future, further allowing the biosynthesis of novel molecular structures
with unique properties. 相似文献
464.
Characterization of epididymal sperm from Spix's yellow‐toothed cavies (Galea spixii Wagler, 1831) recovered by different methods 下载免费PDF全文
Andréia Maria da Silva José Artur Brilhante Bezerra Lívia Batista Campos Érica Camila Gurgel Praxedes Gabriela Liberalino Lima Alexandre Rodrigues Silva 《Acta zoologica》2017,98(3):285-291
The aim of the present study was to characterize the epididymal sperm of Spix's yellow‐toothed cavy (Galea spixii) through two different recovery methods. Nine sexually mature males were euthanized and the complexes, testes–epididymis, were dissected. For each animal, one epididymis was processed by flotation method and the other was processed by retrograde flushing method, both using a TES‐based buffered media. After recovery, we evaluated the sperm for motility, vigour, viability, functional membrane integrity and morphology. Morphometric data from the different sperm regions were evaluated by using an appropriate software. After recovery, both methods provide similar values for all the sperm parameters, aiming the recovery of more than 300 × 106 sperm, presenting >50% motile sperm, with normal morphology and functional membrane. The total sperm length in this sperm was 48.87 ± 0.1, and the sperm head presented 9.4%, on average. A notable characteristic was the prominent acrosome found in the G. spixii sperm. In conclusion, we demonstrate that either flotation or retrograde flushing methods are suitable for the recovery of sperm from cauda epididymis of Spix's yellow‐toothed cavies. 相似文献
465.
Adrian A. Barnett Anita I. Stone Peter Shaw Beatriz Ronchi-Teles Tereza dos Santos-Barnett Natalia C. Pimenta Natalia M. Kinap Wilson R. Spironello Aparecida Bitencourt Gemma Penhorwood Rebecca N. Umeed Tadeu G. de Oliveira Bruna M. Bezerra Sarah A. Boyle Caroline Ross John W. Wenzel 《Austral ecology》2023,48(4):719-742
Optimal foraging theory predicts that well-defended potential foods should be exploited only when energy pay-offs are great. Although stinging hymenopteran nests are both well-defended and predated by primates, their larvae's energy yields rarely have been calculated, and predation-linked foraging behaviours by primates infrequently documented. Based on 58 opportunistic observations of primates raiding wasp nests for larvae, we calculated energetic yields of low- and high-risk wasp nest predation for Cebus albifrons, Saimiri collinsi, S. sciureus and Sapajus apella, and tested predictions derived from optimal foraging theory. We recorded how nests were processed and by which age-sex classes, eaten nest fragment sizes, number of occupied and empty cells, and nest occupancy patterns (percent larvae/pupae, eggs, empty cells). Basal metabolic rate (BMR) calculations showed energetic yields from 15 min foraging on low-risk nests (Polybia quadricincta) would meet energy needed to sustain adult female and male C. albifrons BMR for 4.9 and 4.5 h, respectively; yields from high-risk (Chartergus artifex) nests for 6.5 and 6.2 h; Mischocyttarus sp. nest yields (low risk, but mimetically resembling other wasps) would meet S. collinsi BMR for 2.9 h (female) and 2.3 h (male), and 2.6 and 2.1 h, for the slightly larger S. sciureus, respectively. The Chartergus energetic-yield value is nearly 20% of a 36 g chocolate bar (741 kJ). Our data provide quantitative support for the common assertion that wasp larvae and pupae are high-yield foods for primates. As predicted by optimal foraging, energetic yield is sufficient to offset the risk and pain of being stung. 相似文献
466.
Maria Conceição M. Torres João Carlos Assunção Gilvandete Maria P. Santiago Manoel Andrade‐Neto Edilberto R. Silveira Leticia V. Costa‐Lotufo Daniel P. Bezerra José Delano B. Marinho Filho Francisco Arnaldo Viana Otília Deusdênia L. Pessoa 《化学与生物多样性》2008,5(12):2724-2728
The chemical composition of the leaf essential oil of Croton regelianus collected from wild plants growing in two different sites at Ceará State (Brazil) was analyzed by GC/MS and GC‐FID. Twenty monoterpenoids, representing more than 96% of the chemical composition of the oils, were identified and quantified. The oils showed similar chemical composition but considerable variation in the levels of each constituent. Ascaridole (33.9–17.0%), p‐cymene (22.3–21.6%), and camphor (13.0–3.1%) were the predominant constituents. The monoterpene ascaridole was isolated and characterized by spectroscopic data. The essential oils and the isolated compounds were tested against Aedes aegypti and Artemia sp. larvae, and the root knot nematode Meloidogyne incognita. The bioassay results show that the essential oil of C. regelianus and ascaridole were moderately active against the M. incognita, but strongly effective against both A. aegypti and Artemia sp. larvae. 相似文献