Doppler Detection in Ama Divers of Japan     

Frédéric Lemaître  Kiyotaka Kohshi  Hideki Tamaki  Kasuo Nakayasu  Mesanori Harada  Masanobu Okayama  Yuka Satou  Michiko Hoshiko  Tatsuya Ishitake  Guillaume Costalat  Bernard Gardette 《The Forestry Chronicle》2014,25(3):258-262

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Post-emergent herbicidal activity of cineole derivatives   总被引：1，自引：0，他引：1  

Allan F. M. Barton  Brenton R. Clarke  Bernard Dell  Allan R. Knight 《Journal of pest science》2014,87(3):531-541

Essential oils are being investigated as potential herbicides or to provide leads to new environmentally and socially acceptable herbicides. Novel hydroxy and ester derivatives of 1,8-cineole and 1,4-cineole were synthesised, by chemical and biological methods, and have shown pre-emergence herbicidal activity against annual ryegrass and radish. Effects on post-emergence activity of these derivatives, as well as 1,8-cineole, eucalyptus oil and the carboxylic acids from which the esters were derived, against annual ryegrass and radish, are reported here. Results suggest that reduced root and shoot growth observed in pre-emergence herbicidal bioassays were due to post-emergence activity rather than delayed germination. All tested substances had a dose-dependent, post-emergence herbicidal activity against annual ryegrass and radish with many derivatives showing improved activity relative to 1,8-cineole and high-cineole eucalyptus oil. However, results do not support the postulate that cineole esters would be more active than their respective carboxylic acid and the hydroxy cineole. Phytotoxicity of ester derivatives may be due to metabolic cleavage of the esters to the hydroxy cineole and carboxylic acid within the plant.  相似文献   

非生产天数——提高母猪繁殖群效率的关键     

Bernard Peet 《北方牧业》2014,(3)

正母猪的非生产天数(NPD)是指每个繁殖周期,或每年母猪或青年母猪既非妊娠又非泌乳的天数,它是影响猪群繁殖生产效率最关键的指标。某些记录系统还包括青年母猪从进场到配种的时间,但这段时间的长短与青年母猪的引进程序有关,不同猪场之间存在很大差异,现在只探讨第一胎之后的非生产天数。  相似文献   

Attitudes of Rural Communities Toward Dispersing African Wild Dogs in South Africa     

Daniel M. Parker  Brendan M. Whittington-Jones  Richard T. F. Bernard  Harriet T. Davies-Mostert 《Human Dimensions of Wildlife》2014,19(6):512-522

Subsistence pastoralists often view large carnivores negatively given that any loss of livestock is likely to represent a significant economic cost. Consequently, large carnivore conservation initiatives in rural landscapes should incorporate appropriate human–carnivore conflict mitigation strategies. In this study, structured interviews with local residents (n = 247) were used for determining attitudes toward African wild dogs (Lycaon pictus) among rural communities neighboring two protected areas in KwaZulu-Natal, South Africa. Contrary to expectations, the majority of respondents (58%) were generally positive toward wild dogs. This was probably due to a lack of livestock depredation by wild dogs and relatively high levels of formal education among respondents. Respondents with greater knowledge of wild dogs and conflict mitigation had more positive attitudes, and most were aware of effective husbandry techniques. The positive attitudes observed in these rural communities may benefit wild dog dispersal from natal home ranges and the future conservation of this endangered carnivore.  相似文献   

Adaptation de la teneur en enzymes digestives de l'hepatopancreas de Palaemon serratus (Crustacea,Decapoda), a la composition d'aliments experimentaux     

Alain van Wormhoudt  Hubert J Ceccaldi  Bernard J Martin 《Aquaculture (Amsterdam, Netherlands)》1980,21(1):63-78

The effects of the carbohydrate and protein composition of compound diets on growth rate and on the amylase and protease content of the hepatopancreas have been studied in Palaemon serratus.The best growth rate for animals weighing between 80 and 380 mg is obtained with a diet containing 3.5% carbohydrate and 64% protein. Diets which are very rich in carbohydrate and poor in protein result in poor growth and high mortality; the same is true for foods containing a high concentration of only one protein.Variations in the wet weight of the hepatopanereas and in the total digestive enzymatic activities are linked to variations in the growth rate of the shrimp.Maximal specific amylase activity is reached when assimilable carbohydrate amounts to 2.8%. Maximal specific protease activity is reached when the food protein level reaches 45%. When the amounts of carbohydrate and protein are higher or lower, the values of specific enzymatic proteins diminish.  相似文献   

Use of diet and body condition assessments as intermediate indicators of translocation success in the Critically Endangered Philippine crocodile (Crocodylus mindorensis)     

Joseph C. Brown  Matthew H. Shirley  Amante Yog-yog  Merlijn van Weerd  Marites G. Balbas  Bernard A. Tarun  Cameron D. Siler 《水产资源保护:海洋与淡水生态系统》2021,31(10):2817-2829

1. Intermediate metrics of translocation success are useful for long-lived, slow to mature species where survival and reproduction happen over decades.
2. With fewer than 150 individuals in the wild, the Critically Endangered Philippine crocodile (Crocodylus mindorensis) is one of the most threatened species on Earth. This study presents the first analysis of diet and body condition of wild Philippine crocodiles and headstarted (i.e. captive-reared) individuals released into the wild over the last decade, and uses these results to show how diet and body condition can be pertinent intermediate metrics of translocation success.
3. Analyses of stomach contents revealed 17 different aquatic and terrestrial invertebrate and vertebrate prey species. Interestingly, 70% of Philippine crocodiles showed snails to be the predominent prey type, followed by fish (36.7%), birds (33.3%) and reptiles (33.3%). More than 50% of crocodiles consumed the invasive golden apple snail, a leading agricultural pest. Regardless of crocodile history (wild vs. headstarted) or size class (juvenile vs. adult), no evidence was found for dietary differences in percentage occurrence, percentage composition or prey diversity.
4. Body condition was significantly higher in wild compared with headstarted individuals when analysed together in a pooled group, although neither group differed significantly from the standardized expectation, and headstarted individuals were not significantly different when body condition was derived independently for the two groups.
5. This study provides a working example of how assessing the convergence of diet and body condition between translocated and wild individuals can provide complementary monitoring parameters to demonstrate post-release establishment of translocated crocodylians. The congruent dietary composition and comparable body condition observed in this study suggest that headstarted crocodiles adapt well following release.
6. Crocodylus mindorensis survives in an agricultural landscape and is likely to play an ecologically important role by exploiting invasive species, reinforcing the importance of this species to local communities.

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Diazaquinomycins E–G,Novel Diaza-Anthracene Analogs from a Marine-Derived Streptomyces sp.     

Michael W. Mullowney  Eoghainín ó hAinmhire  Anam Shaikh  Xiaomei Wei  Urszula Tanouye  Bernard D. Santarsiero  Joanna E. Burdette  Brian T. Murphy 《Marine drugs》2014,12(6):3574-3586

As part of our program to identify novel secondary metabolites that target drug-resistant ovarian cancers, a screening of our aquatic-derived actinomycete fraction library against a cisplatin-resistant ovarian cancer cell line (OVCAR5) led to the isolation of novel diaza-anthracene antibiotic diazaquinomycin E (DAQE; 1), the isomeric mixture of diazaquinomycin F (DAQF; 2) and diazaquinomycin G (DAQG; 3), and known analog diazaquinomycin A (DAQA; 4). The structures of DAQF and DAQG were solved through deconvolution of X-Ray diffraction data of their corresponding co-crystal. DAQE and DAQA exhibited moderate LC₅₀ values against OVCAR5 of 9.0 and 8.8 μM, respectively. At lethal concentrations of DAQA, evidence of DNA damage was observed via induction of apoptosis through cleaved-PARP. Herein, we will discuss the isolation, structure elucidation, and biological activity of these secondary metabolites.  相似文献   

Quantifying and simulating carbon and nitrogen mineralization from diverse exogenous organic matters     

Florent Levavasseur  Gwenaelle Lashermes  Bruno Mary  Thierry Morvan  Bernard Nicolardot  Virginie Parnaudeau  Laurent Thuriès  Sabine Houot 《Soil Use and Management》2022,38(1):411-425

The potential contributions of exogenous organic matters (EOMs) to soil organic C and mineral N supply depend on their C and N mineralization, which can be assessed in laboratory incubations. Such incubations are essential to calibrate decomposition models, because not all EOMs can be tested in the field. However, EOM incubations are resource-intensive. Therefore, easily measurable EOM characteristics that can be useful to predict EOM behaviour are needed. We quantified C and N mineralization during the incubation of 663 EOMs from five groups (animal manures, composts, sewage sludges, digestates and others). This represents one of the largest and diversified set of EOM incubations. The C and N mineralization varied widely between and within EOM subgroups. We simulated C and N mineralization with a simple generic decomposition model. Three calibration methods were compared. Individual EOM calibration of the model yielded good model performances, while the use of a unique parameter set per EOM subgroup decreased the model performance, and the use of two EOM characteristics to estimate model parameters gave an intermediate model performance (average RMSE-C values of 32, 99 and 65 mg C g⁻¹ added C and average RMSE-N values of 50, 126 and 110 mg N g⁻¹ added N, respectively). Because of the EOM variability, individual EOM calibration based on incubation remains the recommended method for predicting most accurately the C and N mineralization of EOMs. However, the two alternative calibration methods are sufficient for the simulation of EOMs without incubation data to obtain reasonable model performances.  相似文献   

Hydrogen cyanide production by soil bacteria: Biological control of pests and promotion of plant growth in sustainable agriculture     

Anju SEHRAWAT  Satyavir S. SINDHU  Bernard R. GLICK 《土壤圈》2022,32(1):15-38

Currently, plant diseases and insect infestations are mainly controlled by the extraneous application of pesticides. Unfortunately, the indiscriminate use of such agrochemicals can cause ecological and environmental problems, as well as human health hazards. To obviate the potential pollution arising from the application of agrochemicals, biological control of soilborne pathogens or insect pests using antagonistic microorganisms may be employed. Certain soil bacteria, algae, fungi, plants and insects possess the unique ability to produce hydrogen cyanide(HCN), which plays an important role in the biotic interactions of those organisms. In particular, cyanogenic bacteria have been found to inhibit the growth of various pathogenic fungi, weeds, insects, termites and nematodes. Thus, the use of HCN-producing bacteria as biopesticides offers an ecofriendly approach for sustainable agriculture. The enzyme, HCN synthase,involved in the synthesis of HCN, is encoded by the hcnABC gene cluster. The biosynthetic regulation of HCN, antibiotics and fluorescent insecticidal toxins through the conserved global regulatory GacS/GacA system is elaborated in this review, including approaches that may optimize cyanogenesis for enhanced pest control. In addition, the effects of bacterially synthesized HCN on the production of indole acetic acid, antibiotics and fluorescent insecticidal toxins, 1-aminocyclopropane-1-carboxylate deaminase utilization and phosphate solubilization may result in the stimulation of plant growth. A more detailed understanding of HCN biosynthesis and regulation may help to elaborate the precise role of this compound in biotic interactions and sustainable agriculture.  相似文献   

Performance of field-scale lab vs in situ visible/near- and mid-infrared spectroscopy for estimation of soil properties     

Isabel Greenberg  Michael Seidel  Michael Vohland  Bernard Ludwig 《European Journal of Soil Science》2022,73(1):e13180

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