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1.
Filippi Patrick Whelan Brett M. Vervoort R. Willem Bishop Thomas F. A. 《Precision Agriculture》2022,23(2):578-601
Precision Agriculture - There is considerable interest and value in identifying the gap between crop yields that have actually been achieved, and yields that could have potentially been achieved. A... 相似文献
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Guy Honée Guido F. J. M. Van den Ackerveken Henk W. J. Van den Broek Ton J. Cozijnsen Matthieu H. A. J. Joosten Mirian Kooman-Gersmann Jacques Vervoort Ralph Vogelsang Paul Vossen Jos P. Wubben Pierre J. G. M. De Wit 《Euphytica》1994,79(3):219-225
The fungus Cladosprium fulvum is a biotrophic leaf pathogen of tomato. The fungus develops in the intercellular space without forming specialized feeding structures and does not affect the leaf tissue. The outcome of the C. fulvum-tomato interaction can be described by the gene-for-gene model. Failure of infection is expressed by a hypersensitive response. Two fungal proteins, ECP1 and ECP2, have been isolated and their corresponding genes have been cloned. In a compatible interaction including many physiological races ECP1 and ECP2 are highly produced and a role in pathogenicity is suggestive. The ecp1 gene shows some homology with tumor necrosis factor receptors (TNFRs) while the ecp2 gene shows no homology with sequences known in data bases. However, disruption of one of the two genes showed no reduced pathogenicity of the fungus. Two race-specific elicitors, AVR4 and AVR9, have been isolated and their corresponding genes have been cloned. The avirulence genes Avr4 and Avr9 are only present in C. fulvum avirulent on Cf-4 and Cf-9 cultivars, respectively. The expression of these two genes is, like the expression of the ecp genes, highly induced when the fungus grows in planta. Disruption of the Avr9 gene in wild type avirulent races leads to virulence on tomato genotypes carrying the complementary resistance gene Cf-9. A single base-pair change in the avirulence gene Avr4 leads to virulence on tomato genotypes carrying the Cf-4 resistance gene. Isolation, characterization and possible function of ECP1, ECP2, AVR4, and AVR9 will be discussed. 相似文献
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van Beurden SJ Leroy B Wattiez R Haenen OL Boeren S Vervoort JJ Peeters BP Rottier PJ Engelsma MY Vanderplasschen AF 《Veterinary research》2011,42(1):105
ABSTRACT: Many of the known fish herpesviruses have important aquaculture species as their natural host, and may cause serious disease and mortality. Anguillid herpesvirus 1 (AngHV-1) causes a hemorrhagic disease in European eel, Anguilla anguilla. Despite their importance, fundamental molecular knowledge on fish herpesviruses is still limited. In this study we describe the identification and localization of the structural proteins of AngHV-1. Purified virions were fractionated into a capsid-tegument and an envelope fraction, and premature capsids were isolated from infected cells. Proteins were extracted by different methods and identified by mass spectrometry. A total of 40 structural proteins were identified, of which 7 could be assigned to the capsid, 11 to the envelope, and 22 to the tegument. The identification and localization of these proteins allowed functional predictions. Our findings include the identification of the putative capsid triplex protein 1, the predominant tegument protein, and the major antigenic envelope proteins. Eighteen of the 40 AngHV-1 structural proteins had sequence homologues in related Cyprinid herpesvirus 3 (CyHV-3). Conservation of fish herpesvirus structural genes seemed to be high for the capsid proteins, limited for the tegument proteins, and low for the envelope proteins. The identification and localization of the structural proteins of AngHV-1 in this study adds to the fundamental knowledge of members of the Alloherpesviridae family, especially of the Cyprinivirus genus. 相似文献
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Rainwater harvesting (RWH), the small-scale collection and storage of runoff to augment groundwater stores, has been seen as a solution to the deepening groundwater crisis in India. However, hydrological impacts of RWH in India are not well understood, particularly at the larger catchment-scale. A key element to grasping RWH impact involves understanding the generated recharge variability in time and space, which is the result of variability in rainfall-runoff and efficiency of RWH structures. Yet there are very few reported empirical studies of the impact of RWH. Catchment-scale impacts are best studied using a water balance model, which would require a basic level of field data and understanding of the variability. This study reports the results of a 2-year field study in the 476 km2 semi-arid Arvari River catchment, where over 366 RWH structures have been built since 1985. Difficulties associated with working in semi-arid regions include data scarcity. Potential recharge estimates from seven RWH storages, across three different types and in six landscape positions, were calculated using the water balance method. These estimates were compared with recharge estimates from monitored water levels in 29 dug wells using the water table fluctuation method. The average daily potential recharge from RWH structures varied between 12 and 52 mm/day, while estimated actual recharge reaching the groundwater ranged from 3 to 7 mm/day. The large difference between recharge estimates could be explained through soil storage, local groundwater mounding beneath structures and a large lateral transmissivity in the aquifer. Overall, approximately 7% of rainfall is recharged by RWH in the catchment, which was similar in the comparatively wet and dry years of the field analysis. There were key differences between RWH structures, due to engineering design and location. These results indicate that recharge from RWH affects the local groundwater table, but also has potential to move laterally and impact surrounding areas. However, the greatest weakness in such analysis is the lack of information available on aquifer characteristics, in addition to geology and soil type. 相似文献
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Lohi H Young EJ Fitzmaurice SN Rusbridge C Chan EM Vervoort M Turnbull J Zhao XC Ianzano L Paterson AD Sutter NB Ostrander EA André C Shelton GD Ackerley CA Scherer SW Minassian BA 《Science (New York, N.Y.)》2005,307(5706):81
Epilepsy afflicts 1% of humans and 5% of dogs. We report a canine epilepsy mutation and evidence for the existence of repeat-expansion disease outside humans. A canid-specific unstable dodecamer repeat in the Epm2b (Nhlrc1) gene recurrently expands, causing a fatal epilepsy and contributing to the high incidence of canine epilepsy. Tracing the repeat origins revealed two successive events, starting 50 million years ago, unique to canid evolution. A genetic test, presented here, will allow carrier and presymptomatic diagnosis and disease eradication. Clinicopathologic characterization establishes affected animals as a model for Lafora disease, the most severe teenage-onset human epilepsy. 相似文献
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Goodge JW Vervoort JD Fanning CM Brecke DM Farmer GL Williams IS Myrow PM DePaolo DJ 《Science (New York, N.Y.)》2008,321(5886):235-240
The positions of Laurentia and other landmasses in the Precambrian supercontinent of Rodinia are controversial. Although geological and isotopic data support an East Antarctic fit with western Laurentia, alternative reconstructions favor the juxtaposition of Australia, Siberia, or South China. New geologic, age, and isotopic data provide a positive test of the juxtaposition with East Antarctica: Neodymium isotopes of Neoproterozoic rift-margin strata are similar; hafnium isotopes of approximately 1.4-billion-year-old Antarctic-margin detrital zircons match those in Laurentian granites of similar age; and a glacial clast of A-type granite has a uraniun-lead zircon age of approximately 1440 million years, an epsilon-hafnium initial value of +7, and an epsilon-neodymium initial value of +4. These tracers indicate the presence of granites in East Antarctica having the same age, geochemical properties, and isotopic signatures as the distinctive granites in Laurentia. 相似文献
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S R van Amstel M Henton M A Witcomb B Fabian P Vervoort 《The Onderstepoort journal of veterinary research》1987,54(4):551-552
Bacterial isolations from tracheal and bronchial washes obtained with the aid of a fibreoptic endoscope were carried out over a 7 month period in a feedlot on calves suffering from acute pneumonic pasteurellosis. Pasteurella haemolytica and Pseudomonas aeruginosa represented the majority of isolates. Antibiotic sensitivities of the Pasteurella isolates are reported on. 相似文献
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AGTR2 mutations in X-linked mental retardation 总被引：1，自引：0，他引：1
Vervoort VS Beachem MA Edwards PS Ladd S Miller KE de Mollerat X Clarkson K DuPont B Schwartz CE Stevenson RE Boyd E Srivastava AK 《Science (New York, N.Y.)》2002,296(5577):2401-2403
Two angiotensin II (Ang II)-specific receptors, AGTR1 and AGTR2, are expressed in the mammalian brain. Ang II actions on blood pressure regulation, water electrolyte balance, and hormone secretion are primarily mediated by AGTR1. The function of AGTR2 remains unclear. Here, we show that expression of the AGTR2 gene was absent in a female patient with mental retardation (MR) who had a balanced X;7 chromosomal translocation. Additionally, 8 of 590 unrelated male patients with MR were found to have sequence changes in the AGTR2 gene, including one frameshift and three missense mutations. These findings indicate a role for AGTR2 in brain development and cognitive function. 相似文献
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Joni Rossi Annelies Govaerts Bruno De Vos Bruno Verbist André Vervoort Jean Poesen Bart Muys Jozef Deckers 《CATENA》2009
Southeastern Tanzania serves as a typical example of soil degradation and soil organic carbon (SOC) losses on the African continent. Although sequestration of SOC through aforestation or reforestation proved favorable, these measures are restricted by the ability to produce rapid, cost-effective and precise sampling schemes. The aim of this study is to contribute to a better knowledge of the spatial distribution of soil C in tropical natural and plantation forest. This paper presents sampling strategies for estimating mean SOC values as well as for SOC mapping, based on different methods for SOC determination and on different precision levels. To do so we conducted a carbon variability study in five common forest types of Southeastern Tanzania (coastal dry forest, Miombo woodland, teak plantation, pine plantation and cashew plantation) using conventional statistical methods, as well as geostatistics. In the 5 forest types of this study, SOC stocks in the upper 5 cm ranges between 5 (in the cashew plantation) and 13 (in the coastal forest) t ha− 1. The optimal sampling distance for measuring mean SOC stocks varies between 36 m (in the patchy miombo woodland) and 422 m (in the homogenized cashew plantation). Sample sizes fluctuate between 6 and 72 (1 t ha− 1 precision) for respectively cashew plantation and coastal forest. A rectangular grid with a sample interval of 25 m can be used for SOC mapping with a point kriging estimation error of 3.0 t ha− 1 in the coastal forest, 2.6 t ha− 1 in miombo woodland, 2.2 t ha− 1 in the teak plantation and 1.1 t ha− 1 in the cashew plantation. Since the pine plantation has no spatial structure; samples can be arranged randomly and its best soil map has an average C content attributed over the whole field. Refining the sampling strategy with a new spatial variability study in other forest types can be based on a regular grid with sampling distances of half the range identified in this study. This paper proves that the optimal sampling scheme varies strongly as a result of the different spatial behavior of SOC in forests and depends on the required precision and research question. Only when the right strategy is followed, high standards of precision can be met without economic loss or risk of statistical misinterpretation. 相似文献