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731.
This study analyses drug trafficking associated with fisheries around the globe. Records of vessel interdiction carried out between 2010 and 2017 suggest that the global trade of illicit drugs relies increasingly on fishing vessels. Fishery‐based trafficking is growing. A key obstacle to understanding the scope of this problem is the limited data on activities that are intentionally obscured, such as drug trafficking. Using a Fermi estimation technique for determining unknown values from limited data, we analyse 292 known cases of fishing boats engaged in drug shipment between 2010 and 2017. Results suggest that drug shipment sizes per vessel are becoming smaller over time, even as the total flow of drugs is increasing. Counter‐drug enforcement intensifies this effect, suggesting that drug trafficking networks adapt to interdiction efforts making use of smaller vessels to lower the risk of seizure. The use of fishing vessels in drug trans‐shipment has tripled over the past 8 years to about 15% of the global retail value of illicit drugs. Small‐scale fishers are at risk of turning to drug trade as an economic buffer against poverty, especially in contexts of mounting competition over declining fish stocks or strict marine conservation. At the same time, illicit capital flowing from the narcotics trade into fisheries may be driving over‐capitalization of fisheries and unsustainable resource use, ultimately to the detriment of resource‐dependent coastal communities and marine ecosystems. Future research is needed to better understand whether and how small‐scale fishermen turn to drug trade to counter livelihood risks of various kinds. 相似文献
732.
Maria Zaharieva Negash Geleta Ayana Amin Al Hakimi Satish C. Misra Philippe Monneveux 《Genetic Resources and Crop Evolution》2010,57(6):937-962
Cultivated emmer wheat, Triticum dicoccon Schrank, a tetraploid species with hulled grain, has been largely cultivated during seven millennia in the Middle-East, Central and West Asia, and Europe. It has been largely replaced by hulless species and is now a minor crop, with the exception of some countries like India, Ethiopia and Yemen, where its grain is used for preparing traditional foods. Nutritional qualities and specific taste and flavor of emmer wheat products have led to a recent development of the cultivation in some European countries. Emmer wheat also possesses valuable traits of resistance to pests and diseases and tolerance to abiotic stresses and is increasingly used as a reservoir of useful genes in wheat breeding. In the present article, a review concerning taxonomy, diversity and history of cultivation of emmer wheat is reported. Grain characteristics and valuable agronomic traits are described. Some successful examples of emmer wheat utilization for the development of durum or bread wheat cultivars are examined, and the perspectives in using emmer wheat as health food and for the development of new breeding germplasm are discussed. 相似文献
733.
Variation for stomatal characteristics and water use efficiency among diploid,tetraploid and hexaploid Iranian wheat landraces 总被引:1,自引:0,他引:1
Hamid Khazaei Philippe Monneveux Shao Hongbo Shahram Mohammady 《Genetic Resources and Crop Evolution》2010,57(2):307-314
Wheat is one of the most important crops in the world. Its study has involved anatomy, ecology, physiology, molecular biology,
biotechnology, and cultivation. Knowledge of the relationship of diploid, tetraploid and hexaploid wheat with stomatal characteristics
and water-use efficiency is spare and is subject to argument. The present study was aimed to examine different characteristics
of stomata in 28 Iranian landraces belonging to the species Triticum monococcum (2n = 2x = 14), Triticum durum (2n = 4x = 28) and Triticum aestivum (2n = 6x = 42), respectively and investigated a possible relationship between these characteristics and water use efficiency by pot
cultivation experiments. The results revealed large variation among landraces as well as between the different species for
stomatal frequency and size. The diploid wheat species had the highest stomatal frequency and the lowest stomatal length and
width. The hexaploid species had a lower stomatal frequency than the tetraploid species. A highly significant relationship
was noted between the value of those traits on the adaxial and abaxial surfaces of the leaf. The ratio of adaxial to abaxial
values appeared to be constant for a given species. Both stomatal frequency and size were associated with ploidy level, but
also with the nature of the constituting genomes of the species. A highly significant negative association was found among
accessions between stomatal frequency and size. As a consequence, the variation for stomatal area per unit leaf area was less
than for the other traits. Diploid and hexaploid wheat have significantly higher water use efficiency, compared to tetraploid
wheat. No clear association was found, however, between water use efficiency and stomatal characteristics. 相似文献
734.
Xuhui Wang Philippe Ciais Markus Reichstein Tao Wang 《Soil biology & biochemistry》2010,42(10):1728-1734
Soil respiration (SR) is highly sensitive to future climate change, and particularly to global warming. However, considerable uncertainties remain associated with the temperature sensitivity of SR and its controlling processes. Using 384 field measurement data from 114 published papers and one book, this study quantifies the variation in the seasonal Q10 values of soil respiration, the multiplier by which respiration rates increase for a 10 °C increase in temperature, and its drivers across different sites. No significant correlation between Q10 and mean annual temperature or mean annual precipitation is found when statistically controlling seasonal changes in vegetation activity, deduced from satellite vegetation greenness index observations (normalized difference vegetation index, or NDVI). In contrast, the seasonal amplitude of NDVI is significantly and positively correlated with the apparent Q10 of SR. This result indicates that the variations of seasonal vegetation activity exert dominant control over the variations of the apparent Q10 of SR across different sites, highlighting the ecological linkage between plant physiological processes and soil processes. It further implies that the seasonal variation of vegetation activity may thus dominate the apparent seasonal temperature sensitivity. We conclude that the apparent Q10 value of SR estimated from field measurements is generally larger than the intrinsic temperature sensitivity of soil organic matter decomposition, and thus cautions should be taken when applying apparent Q10 values directly in ecosystem models. Our regression analysis further shows that when the amplitude of NDVI variation approximates 0 (and thus when the seasonality in vegetation activity is marginal), the residual Q10 of SR for soil temperature measured at 5 cm depth is about 1.5. 相似文献
735.
BACKGROUND: The neonicotinoid class of insecticides is a key component of pest management strategies used by stone fruit producers in Europe. Neonicotinoids are currently one of the most important tools for control of the peach‐potato aphid (Myzus persicae). Overreliance on neonicotinoids has led to the development of resistance through a combination of metabolic and target‐site resistance mechanisms in individual aphids. A resistance monitoring project was conducted by Syngenta in 2010 to determine the resistance status of M. persicae populations collected from France and Spain, and to determine the frequency of the target‐site mutation in those populations. RESULTS: Resistance monitoring suggests that resistance to neonicotinoids is relatively widespread in populations of M. persicae collected from peach orchards in the Languedoc‐Roussillon, Provence‐Alpes‐Cote d'Azur and Rhone‐Alpes regions of France, and resistance can be associated with the frequency of the target‐site mutation (R81T). The R81T mutation in its heterozygous form is also present in Spanish populations and is associated with neonicotinoid resistance. CONCLUSION: The widespread nature of neonicotinoid resistance in southern France and the potential for resistance development in northern Spain highlight the need for a coordinated management strategy employing insecticides with different modes of action to reduce the selection pressure with neonicotinoids. Copyright © 2011 Society of Chemical Industry 相似文献
736.
R Bouckaert P Lemey M Dunn SJ Greenhill AV Alekseyenko AJ Drummond RD Gray MA Suchard QD Atkinson 《Science (New York, N.Y.)》2012,337(6097):957-960
There are two competing hypotheses for the origin of the Indo-European language family. The conventional view places the homeland in the Pontic steppes about 6000 years ago. An alternative hypothesis claims that the languages spread from Anatolia with the expansion of farming 8000 to 9500 years ago. We used Bayesian phylogeographic approaches, together with basic vocabulary data from 103 ancient and contemporary Indo-European languages, to explicitly model the expansion of the family and test these hypotheses. We found decisive support for an Anatolian origin over a steppe origin. Both the inferred timing and root location of the Indo-European language trees fit with an agricultural expansion from Anatolia beginning 8000 to 9500 years ago. These results highlight the critical role that phylogeographic inference can play in resolving debates about human prehistory. 相似文献
737.
738.
It is not known whether brown dwarfs [stellar-like objects with masses less than the hydrogen-burning limit, 0.075 solar mass (M)[symbol:see text]] are formed in the same way as solar-type stars or by some other process. Here we report the clear-cut identification of a self-gravitating condensation of gas and dust with a mass in the brown-dwarf regime, made through millimeter interferometric observations. The level of thermal millimeter continuum emission detected from this object indicates a mass ~0.02 to 0.03 M[symbol:see text], whereas the small radius, <460 astronomical units, and narrow spectral lines imply a dynamical mass of 0.015 to 0.02 M[symbol:see text]. The identification of such a pre-brown dwarf core supports models according to which brown dwarfs are formed in the same manner as hydrogen-burning stars. 相似文献
739.
Bosveld F Bonnet I Guirao B Tlili S Wang Z Petitalot A Marchand R Bardet PL Marcq P Graner F Bellaïche Y 《Science (New York, N.Y.)》2012,336(6082):724-727
During animal development, several planar cell polarity (PCP) pathways control tissue shape by coordinating collective cell behavior. Here, we characterize by means of multiscale imaging epithelium morphogenesis in the Drosophila dorsal thorax and show how the Fat/Dachsous/Four-jointed PCP pathway controls morphogenesis. We found that the proto-cadherin Dachsous is polarized within a domain of its tissue-wide expression gradient. Furthermore, Dachsous polarizes the myosin Dachs, which in turn promotes anisotropy of junction tension. By combining physical modeling with quantitative image analyses, we determined that this tension anisotropy defines the pattern of local tissue contraction that contributes to shaping the epithelium mainly via oriented cell rearrangements. Our results establish how tissue planar polarization coordinates the local changes of cell mechanical properties to control tissue morphogenesis. 相似文献
740.
Risi E Agoulon A Allaire F Le Dréan-Quénec'hdu S Martin V Mahl P 《Journal of zoo and wildlife medicine》2012,43(2):248-255
This article presents the results of a study of captive tigers (Panthera tigris) and lions (Panthera leo) vaccinated with a recombinant vaccine against feline leukemia virus; an inactivated adjuvanted vaccine against rabies virus; and a multivalent modified live vaccine against feline herpesvirus, calicivirus, and panleukopenia virus. The aim of the study was to assess the immune response and safety of the vaccines and to compare the effects of the administration of single (1 ml) and double (2 ml) doses. The animals were separated into two groups and received either single or double doses of vaccines, followed by blood collection for serologic response for 400 days. No serious adverse event was observed, with the exception of abortion in one lioness, potentially caused by the incorrect use of the feline panleukopenia virus modified live vaccine. There was no significant difference between single and double doses for all vaccines. The recombinant vaccine against feline leukemia virus did not induce any serologic response. The vaccines against rabies and feline herpesvirus induced a significant immune response in the tigers and lions. The vaccine against calicivirus did not induce a significant increase in antibody titers in either tigers or lions. The vaccine against feline panleukopenia virus induced a significant immune response in tigers but not in lions. This report demonstrates the value of antibody titer determination after vaccination of nondomestic felids. 相似文献