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1.
Plant Biol (Stuttg) ; 23(2): 307-316, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33222359

ABSTRACT

When cultivated and wild plants hybridize, hybrids often show intermediate phenotypic traits relative to their parents, which makes them unfit in natural environments. However, maternal genetic effects may affect the outcome of hybridization by controlling expression of the earliest life history traits. Here, using wild, cultivated and reciprocal crop-wild sunflower (Helianthus annuus L.) hybrids, we evaluated the maternal effects on emergence timing and seedling establishment in the field and on seedling traits under controlled conditions. In the field, we evaluated reciprocal crop-wild hybrids between two wild populations with contrasting dormancy (the high dormant BAR and the low dormant DIA) and one cultivar (CROP) with low dormancy. Under controlled conditions, we evaluated reciprocal crop-wild hybrids between two wild populations (BAR and RCU) and one CROP under three contrasting temperature treatments. In the field, BAR overwintered as dormant seeds whereas DIA and CROP showed high autumn emergence (~50% of planted seeds), resulting in differential overwinter survival and seedling establishment in the spring. Reciprocal crop-wild hybrids resembled their female parents in emergence timing and success of seedling establishment. Under controlled conditions, we observed large maternal effects on most seedling traits across temperatures. Cotyledon size explained most of the variation in seedling traits, suggesting that the maternal effects on seed size have cascading effects on seedling traits. Maternal effects on early life history traits affect early plant survival and phenotypic variation of crop-wild hybrids, thus, they should be addressed in hybridization studies, especially those involving highly divergent parents, such as cultivated species and their wild ancestors.


Subject(s)
Helianthus , Life History Traits , Seedlings , Crops, Agricultural/genetics , Helianthus/genetics , Phenotype , Seedlings/genetics
2.
J Phys Condens Matter ; 31(40): 405901, 2019 Oct 09.
Article in English | MEDLINE | ID: mdl-31247610

ABSTRACT

Usually, the measurements of electronic and magnetic properties of superconducting samples are carried out under a constant temperature bath. On the other hand, thermal gradients induce local variation of the superconducting order parameter, and the vortex dynamics can present interesting behaviors. In this work, we solved the time-dependent Ginzburg-Landau equations simulating samples under two different thermal gradients, and considering two values of the Ginzburg-Landau parameter, [Formula: see text]. We find that both parameters, i.e. [Formula: see text] and thermal gradients, play an important role on the vortex dynamics and on the magnetization behavior of the samples.

3.
Anim Cogn ; 21(3): 393-405, 2018 05.
Article in English | MEDLINE | ID: mdl-29532262

ABSTRACT

There is evidence that wild animals are able to recall key locations and associate them with navigational routes. Studies in primate navigation suggest most species navigate through the route network system, using intersections among routes as locations of decision-making. Recent approaches presume that points of directional change may be key locations where animals decide where to go next. Over four consecutive years, we observed how a wild group of bearded capuchin monkeys used a route network system and Change Point locations (CPs) in the Brazilian ecotone of Cerrado-Caatinga. We built 200 daily routes of one wild bearded capuchin group. We used ArcGIS, the Change Point Test, Spatial Analysis in Macroecology (SAM), and statistical models to test the hypothesis that wild bearded capuchins use CPs located along routes in a different fashion than they use the CPs located at intersections of routes. A logistic regression model was used to determine the landscape variables affecting capuchins' directional changes at intersections or along routes. CPs at intersections were important points of travel path changes, whereas CPs along routes represented a zig-zag movement along the routes following the landscape features. CPs at intersections were associated with steeper terrains and shorter distances from important resources, along with better visibility of the home range. Our results support the hypothesis that intersections among routes in the route network system are located at points where monkeys have the best visibility available to make decisions on where to visit next.


Subject(s)
Cebus/physiology , Spatial Navigation , Animals , Appetitive Behavior , Brazil , Cognition , Female , Geography , Locomotion , Logistic Models , Male
4.
Environ Monit Assess ; 189(3): 101, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28185156

ABSTRACT

Wild turnip (Brassica rapa) is a common weed and a close relative to oilseed rape (Brassica napus). The Clearfield® production system is a highly adopted tool which provides an alternative solution for weed management, but its efficiency is threatened by gene transfer from crop to weed relatives. Crop-weed hybrids with herbicide resistance were found in the progeny of a B. rapa population gathered from a weedy stand on the borders of an oilseed rape (B. napus) imidazolinone (IMI)-resistant crop. Interspecific hybrids were confirmed by morphological traits in the greenhouse and experimental field, survival after imazethapyr applications, DNA content through flow cytometry, and pollen viability. The transference of herbicide resistance was demonstrated even in a particular situation of pollen competition between both an herbicide-resistant crop and a non-resistant crop. However, IMI resistance was not found in further generations collected at the same location. These results verify gene transmission from oilseed rape to B. rapa in the main crop area in Argentina where resistant and susceptible varieties are found and seed loss and crop volunteers are common. Hybridization, introgression, and herbicide selection would be associated with the loss of effectiveness of IMI technology.


Subject(s)
Brassica napus/drug effects , Brassica napus/genetics , Brassica rapa/drug effects , Brassica rapa/genetics , Herbicide Resistance/genetics , Herbicides/toxicity , Hybridization, Genetic , Imidazolines/toxicity , Argentina , DNA, Plant/analysis , Environmental Monitoring , Flow Cytometry , Phenotype , Plants, Genetically Modified , Pollen/drug effects , Seeds/drug effects , Weed Control/methods
5.
Cont Lens Anterior Eye ; 39(5): 397-9, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27503126

ABSTRACT

The absence of the eyeball can generate psychosocial and facial harmony changes, such as atrophy of the muscles around it. In these cases, the use of an orthostatic prosthesis with expanding function fosters distension of the tissues for subsequent rehabilitation. This technique consists of making individual ocular prostheses with gradual enlargement of size. The aim of this following clinical report was to describe the technique used in the standing prosthetic rehabilitation of a patient, 73 years old, who underwent enucleation of the right eye as a result of glaucoma. Clinical and laboratory procedures were performed such as impression, adjusting curvature of the sclera, centering the pupil area and processing in heat-cured acrylic resin three prostheses made according to the expansion of the anophthalmic cavity. At the end of treatment, there was a considerable increase of the cavity, allowing for volume replacement similar to that existing in the patient's contralateral orbit, thus generating a satisfactory facial harmony.


Subject(s)
Anophthalmos/rehabilitation , Eye, Artificial , Prosthesis Fitting/methods , Prosthesis Implantation/methods , Aged , Anophthalmos/diagnosis , Anophthalmos/surgery , Equipment Failure Analysis , Female , Humans , Prosthesis Design , Treatment Outcome
6.
Int J Oral Maxillofac Surg ; 41(10): 1291-5, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22578568

ABSTRACT

The objective of this study was to assess and quantify the dimensional error of prototypes produced using multi-slice and cone-beam computed tomography (MSCT and CBCT). Titanium screws were inserted into a dry skull at different points of the midface. The skull was scanned using MSCT (LightSpeed16) with pixel size 0.3 mm and CBCT (i-CAT Cone-Beam 3D) with voxel sizes 0.25 and 0.4 mm. Prototypes were printed (fabricated) using a ZPrinter 310 device. Both the dry skull (gold standard) and the prototypes were measured using a Mitutoyo 3D coordinate measuring system with three perpendicular axes (X, Y, and Z). The prototype produced from MSCT data presented a mean dimensional error of 0.62%; the two models produced with CBCT images yielded errors of 0.74% with voxel size 0.25 mm and 0.82% with voxel size 0.40 mm. No significant differences in dimensional errors were observed across the prototypes (p=0.767; Friedman's non-parametric test). Prototypes produced from CBCT data using voxel sizes of 0.25 and 0.4mm, and also the one produced from MSCT data using pixel size 0.3mm, showed acceptable dimensional errors and can therefore be used in the fabrication of prototypes in dentistry.


Subject(s)
Cone-Beam Computed Tomography , Facial Bones/diagnostic imaging , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Multidetector Computed Tomography , Cadaver , Cone-Beam Computed Tomography/instrumentation , Cone-Beam Computed Tomography/methods , Dimensional Measurement Accuracy , Fiducial Markers , Humans , Multidetector Computed Tomography/instrumentation , Multidetector Computed Tomography/methods , Radiology Information Systems , User-Computer Interface
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