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[学术文献] Pesticides: an update of human exposure and toxicity 进入全文

Archives of Toxicology 期刊

Pesticides are a family of compounds which have brought many benefits to mankind in the agricultural, industrial, and health areas, but their toxicities in both humans and animals have always been a concern. Regardless of acute poisonings which are common for some classes of pesticides like organophosphoruses, the association of chronic and sub-lethal exposure to pesticides with a prevalence of some persistent diseases is going to be a phenomenon to which global attention has been attracted. In this review, incidence of various malignant, neurodegenerative, respiratory, reproductive, developmental, and metabolic diseases in relation to different routes of human exposure to pesticides such as occupational, environmental, residential, parental, maternal, and paternal has been systematically criticized in different categories of pesticide toxicities like carcinogenicity, neurotoxicity, pulmonotoxicity, reproductive toxicity, developmental toxicity, and metabolic toxicity. A huge body of evidence exists on the possible role of pesticide exposures in the elevated incidence of human diseases such as cancers, Alzheimer, Parkinson, amyotrophic lateral sclerosis, asthma, bronchitis, infertility, birth defects, attention deficit hyperactivity disorder, autism, diabetes, and obesity. Most of the disorders are induced by insecticides and herbicides most notably organophosphorus, organochlorines, phenoxyacetic acids, and triazine compounds.

[学术文献] Male chemical cues mediate the female preference for egg deposition site in Rhynchophorus ferrugineus 进入全文

Bulletin of Insectology 期刊

The choice of a suitable oviposition site is critical for the reproductive success of many animals. In insects, oviposition site choice is often driven by chemicals: oviposition-deterring pheromones are well known for many insects, whereas oviposition-stimulating pheromones have only been reported for a few species. Here, we investigate which cues trigger the choice of a deposition site in the Red Palm Weevil, Rhynchophorus ferrugineus (Olivier) (Coleoptera Dryophthoridae), the worst palm pest. Our experiments clearly showed that females prefer to lay eggs in a substrate already used for the same purpose. To provide evidence for cues mediating this preference, we carried out a series of bioassays following a binary-choice test paradigm. Our results showed that neither the presence of eggs nor the polar or apolar compounds extracted from the egg surface affected female preference. Moreover, experiments in which the body of adults was rubbed on the substrate allowed us to exclude that body surface compounds are involved in this process. Bioassays preventing male-substrate contact suggested a role of the male in determining the female’s choice of the oviposition site. Our results suggest the male aggregation pheromone as the best candidate to mediate such female preference. Further studies will be necessary to clarify whether female preference represents a simple by-product of the aggregation pheromone effect or is due to a specific compound of the pheromone that triggers the female behaviour.

[学术文献] What are brochosomes for? An enigma of leafhoppers (Hemiptera, Cicadellidae) 进入全文

Denisia 期刊

Production of brochosomes is an enigmatic trait unique to leafhoppers (Cicadellidae). These curiously structured ultramicroscopic protein-lipid particles are produced in the specialized cells of the Malpighian tubules, but it is unlikely that they are an excretory product. Leafhoppers actively apply brochosomes to their integument and, sometimes, to their egg nests. The small size and intricate surface structure of brochosomes apparently render layers of these particles unwettable with water and sticky honeydew. Another possible function of such coatings is direct or indirect protection against the attachment and germination of fungal spores. It is unlikely that any of the other proposed roles, that include the protection from desiccation, UV light, temperature fluctuations, and from predators and parasites, is the major function of this secretion in the extant Cicadellidae. None of the hypothetical roles of brochosomes has yet been investigated experimentally. All such roles, however, suggest that brochosomes are functionally analogous to the waxy particulate coatings of epidermal origin on the integument and eggs of various insects. The synthesis of secretory products by the Malpighian tubules and the habit of applying these products on the integument may have evolved in the ancestral Cicadomorpha as an adaptation to a subterranean habitat of the immatures. These traits may have been preadaptations to using such products, rather than epidermal waxes, as a protective coating when the immatures of early Membracoidea switched to freeliving. The inadequate knowledge of the properties of brochosomes and complete lack of experimental studies render the current interpretations highly speculative. To fully elucidate the function of brochosomes, future studies should employ diverse experimental and comparative approaches.

[统计数据] Tea Yield in World and Five Continents in 2018 (FAOSTAT) 进入全文

FAO 网站

根据FAOSTAT,最新统计了2018年度全球及五大洲(包括:非洲、东非、中非、非洲南部、西非、美洲、中美洲、南美洲、亚洲、东亚、南亚、东南亚、西亚、欧洲、东欧洲、南欧、大洋洲、美拉尼西亚、世界)茶叶产量,数据详见表 Tea Yield in World and Five Continents in 2018(FAOSTAT)。

[学术文献] Repellency and some biological effects of different ultrasonic waves on Mediterranean flour moth, Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae) 进入全文

Journal of Stored Products Research 期刊

Ephestia kuhniella is one of the most important stored pests in the world. Repellency and biological effects of various ultrasonic signals with different frequencies and wave shapes on adult, larvae and pupae of the pest were studied in laboratory conditions. Choice and non-choice tests was performed by an invented signal generator device. In choice tests, different ultrasonic frequencies, and for each frequency, four different waveforms were emitted by the device and numbers of repelled moths were separately calculated. Dispersion patterns, weight and survival of the pest treated by the ultrasound were compared with control in non-choice tests. The choice tests indicated that shape and frequency of ultrasound significantly affected evasive behavior of the moths by the waves. The highest repellency effects of ultrasound were observed at frequencies of 43–45 kHz and wave shapes of Sin (x) and Cos (x). Male moths significantly were more affected by the ultrasound. In non-choice test, weights of the pest larvae and pupae and the larvae survival were significantly reduced when they treated by ultrasound with frequency 40–45 kHz and Sin (x) wave shape that emitted by specific pattern. Also, our findings showed that the larvae and adults considerably tend to avoid from the ultrasound source. Results of the study can be applied for control of the pest in store locations or silage.

[科技图书] Functional Surfaces in Biology:Little Structures with Big Effects (Volume 1) 进入全文

SpringerLink 网站

This book is devoted to the rapidly growing area of science dealing with structure and properties of biological surfaces in their relation to particular function(s). This volume, written by a team of specialists from different disciplines, covers various surface functions such as protection, defense, water transport, anti-wetting, self cleaning, light reflection and scattering, and acoustics. Because biological surfaces have a virtually endless potential of technological ideas for the development of new materials and systems, inspirations from biology could also be interesting for a broad range of topics in surface engineering.

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