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Application of the thermal sum concept was developed to determine the optimal harvesting stage of new banana hybrids to be grown for export. It was tested on two triploid hybrid bananas, FlhorBan 916 (F916) and FlhorBan 918 (F918), created by CIRAD's banana breeding programme, using two different approaches. The first approach was used with F916 and involved calculating the base temperature of bunches sampled at two sites at the ripening stage, and then determining the thermal sum at which the stage of maturity would be identical to that of the control Cavendish export banana. The second approach was used to assess the harvest stage of F918 and involved calculating the two thermal parameters directly, but using more plants and a longer period. Using the linear regression model, the estimated thermal parameters were a thermal sum of 680 degree-days (dd) at a base temperature of 17.0 °C for cv. F916, and 970 dd at 13.9 °C for cv. F918. This easy-to-use method provides quick and reliable calculations of the two thermal parameters required at a specific harvesting stage for a given banana variety in tropical climate conditions. Determining these two values is an essential step for gaining insight into the agronomic features of a new variety and its potential for export.  相似文献   
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Most long-path remote spectroscopic studies of the atmosphere rely on ambient light or narrow-band lasers. High-power femtosecond laser pulses have been found to propagate in the atmosphere as dynamically self-guided filaments that emit in a continuum from the ultraviolet to the infrared. This white light exhibits a directional behavior with enhanced backward scattering and was detected from an altitude of more than 20 kilometers. This light source opens the way to white-light and nonlinear light detection and ranging applications for atmospheric trace-gas remote sensing or remote identification of aerosols. Air ionization inside the filaments also opens promising perspectives for laser-induced condensation and lightning control. The mobile femtosecond-terawatt laser system, Teramobile, has been constructed to study these applications.  相似文献   
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Whether dispersal limitation and phylogenetic conservatism influence soil species assemblages is still a debated question. We hypothesized that spatial and phylogenetic patterns influence communities in a hump-backed fashion, maximizing their impact at intermediate spatial and phylogenetic distances. Species–environment relationships are blurred by dispersal limitation and restricted habitat choice at long and short spatial distances, respectively (Hypothesis 1). Co-occurrence of species/traits is limited by divergent evolution of species/traits and competitive exclusion at long and short phylogenetic distances, respectively (Hypothesis 2). Springtails were sampled over a wide array of environmental gradients, between-sample distance varying from a few cm to several km. We compared communities using species composition, habitat features, and geo-localization. We compared species using co-occurrence, habitat preference, traits and phylogeny. Mantel tests identified which factors contributed the best to species/traits assemblages. Within the studied area, species composition was influenced by habitat more than space. Traits displayed a strong phylogenetic signal, but they contributed less than habitat preferences to species co-occurrence. Species–environment relationships were better displayed within a 200 m distance, supporting Hypothesis 1. Occurrence-habitat preference relationships were better displayed at family level, supporting Hypothesis 2.  相似文献   
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The effect of uterine infection on size and follicular fluid composition of the largest follicle was studied in buffalo. Reproductive tracts were collected from 102 graded Murrah buffaloes at an abattoir. Uterine infection was diagnosed by physical examination of uterine mucus, white side test and uterine cytology. Samples with pus‐containing mucus, positive reaction on white side test and/or >5% neutrophils were considered to be positive for uterine infection. Diameter of the largest follicle was measured, and follicular fluid was aspirated and assayed for nitric oxide (NO), ascorbic acid (AA), cholesterol, oestradiol (E2) and progesterone (P4). Infected buffaloes had smaller‐sized (p < 0.0001) largest follicles than non‐infected buffaloes. Follicular fluid collected from the largest follicle in infected buffaloes had greater (p < 0.0001) NO and P4 concentrations coincident with lesser AA (p < 0.001), cholesterol (p < 0.0001) and E2 (p < 0.0001) concentrations. Results indicated that uterine infection has an inhibitory effect on growth of the largest follicle in buffalo. The changes in follicular fluid composition in infected buffaloes suggest that the direct effect of uterine infection on ovarian function may be mediated through an alteration in the follicular microenvironment. Greater NO and lesser AA concentrations in the follicular fluid of infected animals are novel findings.  相似文献   
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Purpose The purpose of this study was to evaluate the efficacy of an aqueous calcineurin inhibitor, SCY‐641, in the treatment of naturally occurring canine immune‐mediated keratoconjunctivitis sicca (KCS). Methods A randomized, double‐masked, placebo‐controlled clinical study of 56‐day duration was performed in dogs with naturally occurring immune‐mediated KCS assigned to treatment with either topical twice‐daily aqueous calcineurin inhibitor solution (SCY‐641) or artificial tears (placebo) by the study administrator. Clinical examination and Schirmer tear tests (STT) were performed prior to therapy and at days 7, 14, 28, and 56 after initiation of treatment. Results Twenty dogs were enrolled in the study with ten receiving placebo and 10 receiving SCY‐641 in one or both eyes. No adverse effects were noted with any treatment. There were no significant differences in mean STT values in dogs in group either at day 0 (prior to therapy) or after 7 days of treatment. At 14, 28, and 56 days after initiation of treatment, mean STT and increase in STT over baseline in dogs treated with SCY‐641 were significantly higher than in dogs treated with placebo (P < 0.04). Conclusions SCY‐641 was well tolerated by dogs with naturally occurring KCS, and by 14 days after initiating therapy, dogs treated with SCY‐641 had significantly higher STT than placebo‐treated dogs. These preliminary results indicate that topical SCY‐641, in a stable clear aqueous solution, is efficacious in a spontaneous model of KCS and warrants further evaluation as a treatment of immune‐mediated KCS.  相似文献   
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