Assessing the effect of selection with deltamethrin on biological parameters and detoxifying enzymes in Aedes aegypti (L.)          下载免费PDF全文

Leslie C Alvarez‐Gonzalez  Arelis Briceño  Gustavo Ponce‐Garcia  O Karina Villanueva‐Segura  Jesus A Davila‐Barboza  Beatriz Lopez‐Monroy  Selene M Gutierrez‐Rodriguez  Yamili Contreras‐Perera  Iram P Rodriguez‐Sanchez  Adriana E Flores 《Pest management science》2017,73(11):2287-2293

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Application of an indirect ELISA to milk samples to identify cows with Mycoplasma bovis mastitis   总被引：1，自引：0，他引：1  

Byrne WJ  Ball HJ  Brice N  McCormack R  Baker SE  Ayling RD  Nicholas RA 《The Veterinary record》2000,146(13):368-369

An indirect ELISA was used to detect antibodies to Mycoplasma bovis in milk samples collected from a herd with M bovis mastitis. Antibodies were detected in samples from nine cows which had developed clinical M bovis mastitis. Milk from only three consistently antigen-negative cows tested positive for M bovis antibodies. These results indicate the potential value of the indirect ELISA for the detection of cows which have recently developed M bovis mastitis during the early stages of an outbreak.  相似文献   

Comparison of a new device for blood sampling in cats with a vacuum tube collection system - plasma biochemistry, haematology and practical usage assessment     

Reynolds BS  Boudet KG  Faucher MR  Germain C  Geffre A  Lefebvre HP 《Journal of Feline Medicine and Surgery》2007,9(5):382-386

Using paediatric devices to collect venous blood from a cephalic vein in cats offers numerous practical advantages over traditional jugular venepuncture and vacuum closed systems: minimal restraint is required; there is minimal risk of serious injury to the cat; the discomfort associated with venepuncture is reduced by the use of small diameter (25 gauge) needles; very small volumes (200 microl) of blood are extracted; and the risk of vein collapse or haematoma is low. The aim of this study was to compare the haematological and plasma chemistry results obtained from six healthy cats using the two sampling techniques. Five plasma biochemical analytes were measured and a complete haematological examination was performed on each specimen. No clinically relevant difference between the two blood sampling techniques was observed for any variable, indicating that paediatric devices provide a useful alternative to vacuum tubes for venous blood collection in the cat.  相似文献   

Sustainable use of non-timber forest products: Impact of fruit harvesting on Pentadesma butyracea regeneration and financial analysis of its products trade in Benin     

Carolle Avocèvou-Ayisso  Brice Sinsin  Anselme Adégbidi  Gatien Dossou  Patrick Van Damme 《Forest Ecology and Management》2009

Pentadesma butyracea Sabine (Clusiaceae) is a multi-purpose tree that provides non-timber forest products (NTFPs). In particular, fruit almonds can be transformed into butter for cooking and cosmetics. During the present study, the following hypotheses were tested: (i) diameter structure of P. butyracea populations is independent of its fruit gathering intensity; (ii) P. butyracea seedling and sapling density and origin are independent of its fruit gathering intensity; (iii) P. butyracea fruit gathering and processing of its almonds are profitable activities and (iv) P. butyracea fruit collectors and almond transformers are receiving the lowest marketing margins in the commercial channel. The class distribution in the low-intensity harvesting sites showed a typical inverse J-shaped curve whereas the high-intensity harvesting ones showed an almost bell curve (G² = 23.93, p = 0.0008). After data analysis, all hypotheses turned out to be wrong except the hypothesis (iii). In order to assess the effects of fruit harvesting on natural regeneration of P. butyracea, we compared seedling and sapling density of regeneration originating from seeds and roots suckers in plots that had been differentiated according to fruit harvesting intensity. These plots were laid out in riparian forests, which are the natural habitats for the species in Benin. Observed seedling and sapling density was high (13,872 ± 7886 seedlings and saplings/ha) in low-intensity harvesting sites but very low (4200 ± 3810 seedlings and saplings/ha) in high-intensity harvesting sites (F = 17.16; p = 0.0006). However, there was no significant difference between root sucker density in either type of harvesting site (F = 0.79; p = 0.3861). Collection of P. butyracea fruits and subsequent processing of its almonds into butter is an important source of income for women involved in these activities. Commercial margin analysis showed that these women involved in almonds and butter trade, far from being exploited by traders, recuperate between 49% and 80% of the price paid by the consumer, depending on the quality of the product and the length of commercial channel used.  相似文献   

Impact of season, stem diameter and intensity of debarking on survival and bark re-growth pattern of medicinal tree species, Benin, West Africa   总被引：1，自引：0，他引：1  

Claire Delvaux  Brice Sinsin 《Biological conservation》2010,143(11):2664-2671

Bark is a greatly coveted non-timber forest product (NTFP). Its overexploitation from medicinal tree species threatens an essential source of medication for rural populations. Despite the relevance of bark, not much information is available on the ecological impact of bark harvesting. In Benin, West Africa, we investigated how various harvesting techniques affect the bark re-growth of 12 tree species and the survival of debarked trees. Trees were debarked following a combination of three factors: (i) season of bark harvesting (dry or rainy season), (ii) size class of the tree (three stem diameter classes) and (iii) intensity of debarking (seven different percentages of trunk circumference debarked). Measurements of edge growth and survival were taken every 6 months during 2 years. Ring-barking (100% of trunk circumference debarked) did not allow the sustainable exploitation of any species, while all trees with 75% of debarked circumference remained alive and produced edge growth. Whatever the bark harvesting technique, 5 out of the 12 species had a bark recovery rate below 1 cm/year, rendering the wound closure very unlikely. On the other hand, five species showed good to very good bark recovery rates (>7 cm/year) and for these species the combination of debarking factors (season, dbh and intensity) allowing the highest edge growth was determined. This experimental bark stripping revealed the complexities involved in decision-making for sustainable tree management. Studying the patterns of bark recovery rates provides a relevant tool to assess for each species the delay for achieving closure of a specific wound area.  相似文献   

Timing and magnitude of C partitioning through a young loblolly pine (Pinus taeda L.) stand using 13C labeling and shade treatments     

Warren JM  Iversen CM  Garten CT  Norby RJ  Childs J  Brice D  Evans RM  Gu L  Thornton P  Weston DJ 《Tree physiology》2012,32(6):799-813

The dynamics of rapid changes in carbon (C) partitioning within forest ecosystems are not well understood, which limits improvement of mechanistic models of C cycling. Our objective was to inform model processes by describing relationships between C partitioning and accessible environmental or physiological measurements, with a special emphasis on short-term C flux through a forest ecosystem. We exposed eight 7-year-old loblolly pine (Pinus taeda L.) trees to air enriched with (13)CO(2) and then implemented adjacent light shade (LS) and heavy shade (HS) treatments in order to manipulate C uptake and flux. The impacts of shading on photosynthesis, plant water potential, sap flow, basal area growth, root growth and soil CO(2) efflux rate (CER) were assessed for each tree over a 3-week period. The progression of the (13)C label was concurrently tracked from the atmosphere through foliage, phloem, roots and surface soil CO(2) efflux. The HS treatment significantly reduced C uptake, sap flow, stem growth and fine root standing crop, and resulted in greater residual soil water content to 1 m depth. Soil CER was strongly correlated with sap flow on the previous day, but not the current day, with no apparent treatment effect on the relationship. Although there were apparent reductions in new C flux belowground, the HS treatment did not noticeably reduce the magnitude of belowground autotrophic and heterotrophic respiration based on surface soil CER, which was overwhelmingly driven by soil temperature and moisture. The (13)C label was immediately detected in foliage on label day (half-life = 0.5 day), progressed through phloem by Day 2 (half-life = 4.7 days), roots by Days 2-4, and subsequently was evident as respiratory release from soil which peaked between Days 3 and 6. The δ(13)C of soil CO(2) efflux was strongly correlated with phloem δ(13)C on the previous day, or 2 days earlier. While the (13)C label was readily tracked through the ecosystem, the fate of root C through respiratory, mycorrhizal or exudative release pathways was not assessed. These data detail the timing and relative magnitude of C flux through various components of a young pine stand in relation to environmental conditions.  相似文献   

Effects of intravenous, low-dose ketamine-diazepam sedation on the results of hematologic, plasma biochemical, and coagulation analyses in cats     

Reynolds BS  Geffré A  Bourgès-Abella NH  Vaucoret S  Mourot M  Braun JP  Trumel C 《Journal of the American Veterinary Medical Association》2012,240(3):287-293

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The CIDA-QUEST large-scale survey of Orion OB1: evidence for rapid disk dissipation in a dispersed stellar population     

Briceño C  Vivas AK  Calvet N  Hartmann L  Pacheco R  Herrera D  Romero L  Berlind P  Sánchez G  Snyder JA  Andrews P 《Science (New York, N.Y.)》2001,291(5501):93-96

We are conducting a large-scale, multiepoch, optical photometric survey [Centro de Investigaciones de Astronomia-Quasar Equatorial Survey Team (CIDA-QUEST)] covering about 120 square degrees to identify the young low-mass stars in the Orion OB1 association. We present results for an area of 34 square degrees. Using photometric variability as our main selection criterion, as well as follow-up spectroscopy, we confirmed 168 previously unidentified pre-main sequence stars that are about 0.6 to 0.9 times the mass of the sun (Mo), with ages of about 1 million to 3 million years (Ori OB1b) and about 3 million to 10 million years (Ori OB1a). The low-mass stars are spatially coincident with the high-mass (at least 3 Mo) members of the associations. Indicators of disk accretion such as Halpha emission and near-infrared emission from dusty disks fall sharply from Ori OB1b to Ori OB1a, indicating that the time scale for disk dissipation and possibly the onset of planet formation is a few million years.  相似文献   

Illumination of the melanopsin signaling pathway     

Panda S  Nayak SK  Campo B  Walker JR  Hogenesch JB  Jegla T 《Science (New York, N.Y.)》2005,307(5709):600-604

In mammals, a small population of intrinsically photosensitive retinal ganglion cells (ipRGCs) plays a key role in the regulation of nonvisual photic responses, such as behavioral responses to light, pineal melatonin synthesis, pupillary light reflex, and sleep latency. These ipRGCs also express melanopsin (Opn4), a putative opsin-family photopigment that has been shown to play a role in mediating these nonvisual photic responses. Melanopsin is required for the function of this inner retinal pathway, but its precise role in generating photic responses has not yet been determined. We found that expression of melanopsin in Xenopus oocytes results in light-dependent activation of membrane currents through the Galpha(q)/Galpha(11) G protein pathway, with an action spectrum closely matching that of melanopsin-expressing ipRGCs and of behavioral responses to light in mice lacking rods and cones. When coexpressed with arrestins, melanopsin could use all-trans-retinaldehyde as a chromophore, which suggests that it may function as a bireactive opsin. We also found that melanopsin could activate the cation channel TRPC3, a mammalian homolog of the Drosophila phototransduction channels TRP and TRPL. Melanopsin therefore signals more like an invertebrate opsin than like a classical vertebrate rod-and-cone opsin.  相似文献   

A comparison of summer and winter measurements of atmospheric nitrogen and sulphur compounds     

K. G. Anlauf  J. W. Bottenheim  K. A. Brice  H. A. Wiebe 《Water, air, and soil pollution》1986,30(1-2):153-160

Summer and winter concentrations of acidic atmospheric species and their precursors were measured in central Ontario. Large seasonal differences in concentrations were observed for some species. The concentrations of primary emission species, S0₂ and NO_x, were much larger in winter, whereas 0₃ and aerosol S0₄ were much reduced. HN0₃, PAN and aerosol N0₃ showed little seasonal change; PAN represented about 30% of the total oxidized nitrate. During pollution episodes and in summer, the molar ratio of nitrate (aerosol N0₃ plus HN0₃) to aerosol S0₄ was about 0.1 to 0.2; however, during winter, this molar ratio was about 1 to 2.  相似文献