493 research outputs found
Pest management and biodiversity in organic fruit production: the case of apple orchards
Numerous pesticide applications are required for orchard protection, regardless of the guidelines. Organic fruit production (OFP) mainly relies on the use of mineral fungicides and microbiological or naturally-occurring insecticides. The environmental impact of this type of production does not significantly differ from that of conventional production when assessed in terms of synthetic indicators. However, the abundance of earthworms, as well as the abundance and specific richness of arthropod pests and beneficials in the orchards and surrounding hedges, is greater in OFP than in conventional orchards. Generalist predators are usually less affected by OFP compounds than by the chemical pesticides applied in conventional orchards. OFP also benefits avian communities, and above all, insectivorous birds, for which organic orchards offer a suitable habitat similar to that of undisturbed natural areas. In addition to this general trend, discrepancies may be observed in the protection responses of different insect groups. The abundance of hymenopteran parasitoids is the lowest in organic orchards in which outbreaks of phytophagous mites are also recorded in relation to the intensive use of sulphur for scab protection. Biological insecticides often act in ways that are similar to those of chemical ones, and the restricted choice of available compounds is likely to induce resistance selection in insect pests. Although maintaining biodiversity is not a direct result of the implementation of OFP guidelines, it seems to be widely considered as an option by organic growers, both alone and as a complementary tool for pest regulation
La rĂ©action dâhĂ©magglutination (RĂ©action de Middlebrook-Dubos ) dans la paratuberculose bovine (EntĂ©rite chronique hypertrophiante, maladie de Johne)
Gernez-Rieux Charles, Tacquet Albert, Gaumont R., Verge Jean, Cauchy Laurent. La réaction d'hémagglutination (Réaction de Middlebrook-Dubos) dans la paratuberculose bovine (Entérite chronique hypertrophiante, maladie de Johne). In: Bulletin de l'Académie Vétérinaire de France tome 103 n°9, 1950. pp. 465-468
An offlineâonline Web-GIS Android application for fast data acquisition of landslide hazard and risk
Regional landslide assessments and mapping have been
effectively pursued by research institutions, national and local
governments, non-governmental organizations (NGOs), and different stakeholders for some time, and a wide range
of methodologies and technologies have consequently been proposed. Land-use
mapping and hazard event inventories are mostly created by remote-sensing
data, subject to difficulties, such as accessibility and terrain, which need
to be overcome. Likewise, landslide data acquisition for the field
navigation can magnify the accuracy of databases and analysis. Open-source
Web and mobile GIS tools can be used for improved ground-truthing of
critical areas to improve the analysis of hazard patterns and triggering
factors. This paper reviews the implementation and selected results of a
secure mobile-map application called ROOMA (Rapid OfflineâOnline Mapping
Application) for the rapid data collection of landslide hazard and risk.
This prototype assists the quick creation of landslide inventory maps (LIMs)
by collecting information on the type, feature, volume, date, and patterns of
landslides using open-source Web-GIS technologies such as Leaflet maps,
Cordova, GeoServer, PostgreSQL as the real DBMS (database management system),
and PostGIS as its plug-in for spatial database management. This application
comprises Leaflet maps coupled with satellite images as a base layer, drawing
tools, geolocation (using GPS and the Internet), photo mapping, and event
clustering. All the features and information are recorded into a
GeoJSON text file in an offline version (Android) and subsequently uploaded
to the online mode (using all browsers) with the availability of Internet.
Finally, the events can be accessed and edited after approval by an
administrator and then be visualized by the general public
Overexpression of Mcl-1 exacerbates lymphocyte accumulation and autoimmune kidney disease in lpr mice
Cell death by apoptosis has a critical role during embryonic development and in maintaining tissue homeostasis. In mammals,
there are two converging apoptosis pathways: the âextrinsicâ pathway, which is triggered by engagement of cell surface âdeath
receptorsâ such as Fas/APO-1; and the âintrinsicâ pathway, which is triggered by diverse cellular stresses, and is regulated by prosurvival
and pro-apoptotic members of the Bcl-2 family of proteins. Pro-survival Mcl-1, which can block activation of the proapoptotic
proteins, Bax and Bak, appears critical for the survival and maintenance of multiple haemopoietic cell types. To
investigate the impact on haemopoiesis of simultaneously inhibiting both apoptosis pathways, we introduced the vavP-Mcl-1
transgene, which causes overexpression of Mcl-1 protein in all haemopoietic lineages, into Faslpr/lpr mice, which lack functional
Fas and are prone to autoimmunity. The combined mutations had a modest impact on myelopoiesis, primarily an increase in the
macrophage/monocyte population in Mcl-1tg/lpr mice compared with lpr or Mcl-1tg mice. The impact on lymphopoiesis was
striking, with a marked elevation in all major lymphoid subsets, including the non-conventional double-negative (DN) T cells
(TCRÎČ+
CD4â
CD8â
B220+
) characteristic of Faslpr/lpr mice. Of note, the onset of autoimmunity was markedly accelerated in Mcl-1tg/lpr
mice compared with lpr mice, and this was preceded by an increase in immunoglobulin (Ig)-producing cells and circulating
autoantibodies. This degree of impact was surprising, given the relatively mild phenotype conferred by the vavP-Mcl-1 transgene
by itself: a two- to threefold elevation of peripheral B and T cells, no significant increase in the non-conventional DN T-cell
population and no autoimmune disease. Comparison of the phenotype with that of other susceptible mice suggests that the
development of autoimmune disease in Mcl-1tg/lpr mice may be influenced not only by Ig-producing cells but also other
haemopoietic cell types
AKT activity orchestrates marginal zone B cell development in mice and humans.
The signals controlling marginal zone (MZ) and follicular (FO) B cell development remain incompletely understood. Here, we show that AKT orchestrates MZ B cell formation in mice and humans. Genetic models that increase AKT signaling in B cells or abolish its impact on FoxO transcription factors highlight the AKT-FoxO axis as an on-off switch for MZ B cell formation in mice. In humans, splenic immunoglobulin (Ig) D <sup>+</sup> CD27 <sup>+</sup> B cells, proposed as an MZ B cell equivalent, display higher AKT signaling than naive IgD <sup>+</sup> CD27 <sup>-</sup> and memory IgD <sup>-</sup> CD27 <sup>+</sup> B cells and develop in an AKT-dependent manner from their precursors in vitro, underlining the conservation of this developmental pathway. Consistently, CD148 is identified as a receptor indicative of the level of AKT signaling in B cells, expressed at a higher level in MZ B cells than FO B cells in mice as well as humans
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