Male germ cell proliferation and apoptosis during the reproductive cycle of captive‐reared Atlantic bluefin tuna Thunnus thynnus (Linnaeus)     

Rosa Zupa  Nicoletta Santamaria  Constantinos C Mylonas  Michele Deflorio  Fernando de la Gándara  Robert Vassallo‐Agius  Chrysovalentinos Pousis  Letizia Passantino  Gerardo Centoducati  Giambattista Bello  Aldo Corriero 《Aquaculture Research》2014,45(10):1733-1736

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Comet 81P/Wild 2 under a microscope     

Brownlee D  Tsou P  Aléon J  Alexander CM  Araki T  Bajt S  Baratta GA  Bastien R  Bland P  Bleuet P  Borg J  Bradley JP  Brearley A  Brenker F  Brennan S  Bridges JC  Browning ND  Brucato JR  Bullock E  Burchell MJ  Busemann H  Butterworth A  Chaussidon M  Cheuvront A  Chi M  Cintala MJ  Clark BC  Clemett SJ  Cody G  Colangeli L  Cooper G  Cordier P  Daghlian C  Dai Z  D'Hendecourt L  Djouadi Z  Dominguez G  Duxbury T  Dworkin JP  Ebel DS  Economou TE  Fakra S  Fairey SA  Fallon S  Ferrini G  Ferroir T  Fleckenstein H  Floss C  Flynn G 《Science (New York, N.Y.)》2006,314(5806):1711-1716

The Stardust spacecraft collected thousands of particles from comet 81P/Wild 2 and returned them to Earth for laboratory study. The preliminary examination of these samples shows that the nonvolatile portion of the comet is an unequilibrated assortment of materials that have both presolar and solar system origin. The comet contains an abundance of silicate grains that are much larger than predictions of interstellar grain models, and many of these are high-temperature minerals that appear to have formed in the inner regions of the solar nebula. Their presence in a comet proves that the formation of the solar system included mixing on the grandest scales.  相似文献   

Characterization of a Potential Nutraceutical Ingredient: Pomegranate (Punica granatum L.) Seed Oil Unsaponifiable Fraction   总被引：1，自引：1，他引：0  

Augusta Caligiani  Francesca Bonzanini  Gerardo Palla  Martina Cirlini  Renato Bruni 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(3):277-283

The chemical fingerprinting of the unsaponifiable fraction of different Punica granatum seed oils was performed in order to evaluate their potential as a functional food ingredient. Qualitative and quantitative determinations of tocopherol, aliphatic alcohol (including policosanol), squalene, phytosterols and triterpene contents were performed by GC-MS. A high yield (3.1–4.2%) of unsaponifiable matter was obtained and consistent levels of squalene (up to 800 mg/kg) and policosanol (118–185 mg/kg) were noticed. β-sitosterol (up to 8069 mg/kg) and cycloartenol (5916–7766 mg/kg) were predominant in phytosterol and triterpene fractions, while β- and δ-tocopherol were the most abundant vitamin E forms. Some minor variations were noticed between samples. From the results obtained, it can be suggested that the seed oil of P. granatum can be considered an interesting alimentary source of substances of nutraceutical value involved in the modulation of cholesterol metabolism.  相似文献   

Induction and identification of a small-granule, high-amylose mutant in cassava (Manihot esculenta Crantz)     

Ceballos H  Sánchez T  Denyer K  Tofiño AP  Rosero EA  Dufour D  Smith A  Morante N  Pérez JC  Fahy B 《Journal of agricultural and food chemistry》2008,56(16):7215-7222

Only two mutations have been described in the literature, so far, regarding starch and root quality traits in cassava. This article reports on an induced mutation in this crop, first identified in 2006. Botanical seed from five different cassava families were irradiated with gamma rays. Seed was germinated, transplanted to the field (M1 plants), and self-pollinated to produce the M2 generation. Abnormal types regarding starch granule morphology were identified during the single plant evaluation of M2 genotypes. To confirm these characteristics, selected genotypes were cloned and a second evaluation, based on cloned plants obtained from vegetative multiplication, was completed in September 2007. Two M2 genotypes presented small starch granules, but only one could be fully characterized, presenting a granule size of 5.80 +/- 0.33 microm compared with three commercial clones with granule sizes ranging from 13.97 +/- 0.12 to 18.73 +/- 0.10 microm and higher-than-normal amylose content (up to 30.1% in cloned plants harvested in 2007, as compared with the typical values for "normal" cassava starch of around 19.8%). The gels produced by the starch of these plants did not show any viscosity when analyzed with the rapid viscoanalyzers (5% suspension), and the gels had low clarity. Low viscosity could be observed at higher concentrations (8 or 10% suspensions). Preliminary results suggest that the mutation may be due to a lesion in a gene encoding one of the isoforms of isoamylase (probably isa1 or isa2).  相似文献   

Study of a germplasm collection of loquat (Eriobotrya japonica Lindl.) by multivariate analysis     

José Martínez-Calvo  Ana Delia Gisbert  M. Carmen Alamar  Rosa Hernandorena  Carlos Romero  Gerardo Llácer  María L. Badenes 《Genetic Resources and Crop Evolution》2008,55(5):695-703

Loquat species (Eriobotrya japonica Lindl.) originated in China, later was introduced in Japan. However, introduction in Europe occurred much later, in 18th century, it was introduced as an ornamental tree. Since then, the species was very well adapted to the Mediterranean climate, mainly in South East of Spain, where is located more than 50% of total European crop production. A European Project titled ‘Conservation, evaluation and collection of underutilized fruit species’ supported surveys and collection of plant material from these species in the Mediterranean basin countries. One of these surveys resulted in a germplasm collection of loquat established at IVIA, Valencia, Spain. This collection is being extended with new accessions collected across the world, currently the collection have 123 accessions under study. Germplasm management needs first a characterization of the plant material introduced and second diversity studies into the collection that could point out the variability pattern, to establish groups of accessions with similar traits and the most significant variables. These results allow organizing the information gathered for further uses. In this paper, 62 accessions from the IVIA germplasm collection were studied. Results from 43 variables were gathered and data studied by multivariate analysis. The analysis allowed summarizing the data tables with new variables containing most of the information. These results along with those obtained in the coming years will allow define a nuclear collection (minimum number of accessions that contained all the variability present in the collection).  相似文献   

Effect of light limitation on the water quality,bacterial counts and performance of Litopenaeus vannamei postlarvae reared with biofloc at low salinity          下载免费PDF全文

Héctor M Esparza‐Leal  Ely S López‐Álvarez  Jesús T Ponce‐Palafox  Josué A Melendrez‐Soto  Marco A Medina‐Astorga  Antonio Luna‐González  Wenceslao Valenzuela‐Quiñónez  Píndaro Álvarez‐Ruiz  Gerardo Rodríguez‐Quiroz 《Aquaculture Research》2017,48(8):4371-4379

The aim of this study was to evaluate the effect of light limitation on the water quality, bacterial counts and performance of Litopenaeus vannamei postlarvae reared with biofloc at low salinity (≈9 g L^?1). Two treatments were designed: T₁ = culture with natural sunlight and T₂ = culture in darkness. After 28 days, in both treatments, the final weight of shrimp was over 0.6 g with a specific growth rate over 7.4% d^?1, and a survival rate over 70%. In both treatments, Vibrio sp. concentration presented low values (culture with natural sunlight = 0.1 to 9.9 × 10² CFU mL^?1, culture in darkness = 0.4 to 11.7 × 10² CFU mL^?1) and Bacillus sp. had high values (culture with natural sunlight = 0.7 to 66.0 × 10⁴ CFU mL^?1, culture in darkness = 0.7 to 65.8 × 10⁴ CFU mL^?1). All water quality parameters remained within the ranges suitable for shrimp culture, except for alkalinity during the first stage of the study. Although in some sampling periods some significant differences were found in bacterial counts and water quality parameters, shrimp productive performance under culture with biofloc at low salinity was not affected significantly by light limitation.  相似文献   

Receiver operating characteristic-based assessment of a serological test used to detect Johne’s disease in Israeli dairy herds          下载免费PDF全文

Marcelo Chaffer  Ariel L. Rivas  Daniel Elad  Ori Koren  Shlomo Garazi  Gerardo Chowell    Steven J. Schwager 《Canadian journal of veterinary research》2008,72(1):18-26

The overall accuracy of an enzyme-linked immunosorbent assay (ELISA) used to detect Johne's disease at herd level was explored in relation to an imperfect test (fecal culture) in 57 Israeli dairy herds. Receiver-operating characteristic (ROC) analysis indicated an area under the curve (AUC) that corresponded to a test accuracy of 82.0% (69.5% to 90.9%; 95% confidence), with optimized herd sensitivity and herd specificity of 70.4% and 83.3%, respectively; and predictive values of 79.2 (+) and 75.8% (-). The optimal ELISA cutoff was 3.16% (> 3.16% seropositive cows in a herd), which was associated with likelihood ratios (LR) of 4.22 (+LR) and 0.36 (-LR), and post-test probabilities of 0.79 (+) and 0.17 (-). For herds with < or = 200 cows (n = 19 herds), the 95% confidence interval (CI) for the AUC was 0.62-0.97 and the optimal cutoff was 3.33% (HSe = 87.5, HSp = 81.8); for herds with > 200 but < or = 270 cows (n = 19 herds), the 95% AUC CI was 0.62-0.97 and the optimal cutoff was 1.13% (HSe = 90.0, HSp = 77.78); and for herds with > 270 cows (n = 19 herds), the 95% AUC CI was 0.69-0.99 and the optimal cutoff was 0.7% (HSe = 100.0, HSp = 70.0). The AUC was not influenced by across-herd prevalence [R2 (adjusted) = 0.0, P > 0.05]. Findings may be applied to facilitate targeted sampling of herds similar to those evaluated. For instance, a test cutoff of 0.76% could be considered for "ruling disease in," while a cutoff of 3.7% could be used for "ruling disease out." Caveats that may influence this analysis are discussed.  相似文献   

Albendazole treatment in laying hens: Egg residues and its effects on fertility and hatchability          下载免费PDF全文

Laura Moreno  Mariana Bistoletti  Hector Fernández  Lucila Cantón  Laura Ceballos  Candela Cantón  Carlos Lanusse  Luis I. Álvarez 《Journal of veterinary pharmacology and therapeutics》2018,41(5):726-733

This work characterized the egg residual concentrations of albendazole (ABZ ) and its sulphoxide (ABZSO ) and sulphone (ABZSO ₂) metabolites and evaluated their effect on egg fertility and hatchability after ABZ treatments to laying hens. Seventy hens were allocated in groups: Group‐1 was the control without treatment; Group‐2 received a single ABZ oral dose (10 mg/kg); Group‐3, ‐4 and ‐5 were treated with ABZ in medicated feed over 7 days at 10, 40, or 80 mg kg^?1 day^?1, respectively. Eggs were analyzed to determine the ABZ /metabolite level by HPLC or subjected to incubation to evaluate the fertility and hatchability. Only ABZSO and ABZSO ₂ metabolites were quantified in egg after ABZ single oral administration with maximum concentrations of 0.47 ± 0.08 and 0.30 ± 0.07 μg/ml, respectively. ABZ and its metabolites were found in eggs after 7‐day ABZ treatments. The egg residue exposure estimated as AUC s (areas under the concentration vs . time curve) were 100.5 (ABZ ), 56.3 (ABZSO ) and 141.3 μg hr g^?1 (ABZSO ₂). ABZ administration did not affect the egg fertility at any dosages. Egg hatchability was not affected by ABZ treatment at 10 mg/kg in medicated feed, but it decreased when the dose was 4–8 times higher. These results should be considered when ABZ is used for deworming laying hens.  相似文献   

Rhizosphere phosphorus depletion by three crops differing in their phosphorus critical levels     

Gerardo Rubio  Valeria Faggioli  Javier D. Scheiner  Flavio H. Gutiérrez‐Boem 《植物养料与土壤学杂志》2012,175(6):810-871

It has been reported for many soils that maize (Zea mays L.) has a higher soil‐P critical level than soybean (Glycine max L.) and sunflower (Helianthus annuus L). The objective of this work was to compare the rhizosphere P depletion in these three species in order to investigate if they differ in their capacity to acquire soil P. Sequential P fractionation and pH were determined in rhizosphere and nonrhizosphere soil samples from field and greenhouse experiments. Neither sunflower (the species with highest rhizosphere acidification) nor soybean or maize showed a significant relationship between P depletion and rhizosphere pH. The labile P fraction and the NaOH‐P_i fraction had lower values in the rhizosphere than in the bulk soil in 38% and 77% of the studied cases, respectively. Sunflower and especially maize presented a more intense P_i depletion than soybean. The comparison between sunflower and maize revealed that neither of them took a clear advantage over the other in terms of P depletion. Rhizosphere P_i depletion was associated with the amount of P acquired by the plants. We conclude that the accessibility to different P pools does not explain the differences in soil‐P critical levels among the three species.  相似文献   

Oldest writing in the New World     

Rodríguez Martínez Mdel C  Ortíz Ceballos P  Coe MD  Diehl RA  Houston SD  Taube KA  Delgado Calderón A 《Science (New York, N.Y.)》2006,313(5793):1610-1614

A block with a hitherto unknown system of writing has been found in the Olmec heartland of Veracruz, Mexico. Stylistic and other dating of the block places it in the early first millennium before the common era, the oldest writing in the New World, with features that firmly assign this pivotal development to the Olmec civilization of Mesoamerica.  相似文献