High-resolution UAV imagery for field olive (Olea europaea L.) phenotyping

Remote sensing techniques based on images acquired from unmanned aerial vehicles (UAVs) could represent an effective tool to speed up the data acquisition process in phenotyping trials and, consequently, to reduce the time and cost of the field work. In this study, we assessed the ability of a UAV equipped with RGB-NIR cameras in highlighting differences in geometrical and spectral canopy characteristics between eight olive cultivars planted at different planting distances in a hedgerow olive orchard. The relationships between measured and estimated canopy height, projected canopy area and canopy volume were linear regardless of the different cultivars and planting distances (RMSE of 0.12 m, 0.44m2 and 0.68m3, respectively). Agood relationship (R2 = 0.95) was found between the pruning mass material weighted on the ground and its volume estimated by aerial images. NDVI measured in February 2019 was related to fruit yield per tree measured in November 2018, whereas no relationships were observed with the fruit yield measured in November 2019 due to abiotic and biotic stresses that occurred before harvest. These results confirm the reliability of UAV imagery and structure from motion techniques in estimating the olive geometrical canopy characteristics and suggest further potential applications of UAVs in early discrimination of yield efficiency between different cultivars and in estimating the pruning material volume

Magnetoelectric ordering of BiFeO3 from the perspective of crystal chemistry

In this paper we examine the role of crystal chemistry factors in creating conditions for formation of magnetoelectric ordering in BiFeO3. It is generally accepted that the main reason of the ferroelectric distortion in BiFeO3 is concerned with a stereochemical activity of the Bi lone pair. However, the lone pair is stereochemically active in the paraelectric orthorhombic beta-phase as well. We demonstrate that a crucial role in emerging of phase transitions of the metal-insulator, paraelectric-ferroelectric and magnetic disorder-order types belongs to the change of the degree of the lone pair stereochemical activity - its consecutive increase with the temperature decrease. Using the structural data, we calculated the sign and strength of magnetic couplings in BiFeO3 in the range from 945 C down to 25 C and found the couplings, which undergo the antiferromagnetic-ferromagnetic transition with the temperature decrease and give rise to the antiferromagnetic ordering and its delay in regard to temperature, as compared to the ferroelectric ordering. We discuss the reasons of emerging of the spatially modulated spin structure and its suppression by doping with La3+.Comment: 18 pages, 5 figures, 3 table

Fetal weight estimation in gestational diabetic pregnancies: comparison between conventional and three-dimensional fractional thigh volume methods using gestation-adjusted projection.

ABSTRACT Objectives To evaluate the accuracy of gestation-adjusted birth-weight estimation using a three-dimensional (3D) fractional thigh volume (TVol) method in pregnant women with gestational diabetes mellitus (GDM), and to compare it with the conventional two-dimensional method of Hadlock et al. Methods Pregnant women with GDM were referred at 34 to 36+6 weeks’ gestation for ultrasound examination. Estimated fetal weight (EFW) was obtained using both the Hadlock and the TVol methods. Using a gestationadjusted projection method, predicted birth weight was compared to actual birth weight at delivery. Results Based on 125 pregnancies, the TVol method with gestation-adjusted projection had a mean (±SD) percentage error in estimating birth weight of −0.01±5.0 (95% CI, −0.96 to 0.98)% while the method of Hadlock with gestation-adjusted projection had an error of 1.28±9.1 (95% CI, −0.33 to 2.87)%. The mean percentage error of the two methods was significantly different (P=0.039), while the random error was not (P=1.0). For the prediction of macrosomia (birth weight ≥4000 g, n=19), sensitivity was 84 and 63% for the TVol and Hadlock methods, respectively (95% CI for difference −2 to 44%, P=0.22) and specificity was 96 and 89% for the TVol andHadlock methods, respectively (95% CI for difference 5–9%, P=0.01). Conclusions In women with GDM, a new method of estimating birth weight based on 3D-TVol measurements performed at 34+0 to 36+6 weeks’ gestation and gestation-adjusted projection of estimated fetal weight, is more accurate than the standard method based on Hadlock’s formula in predicting birth weight. The Correspondence to: Dr F. Prefumo, Maternal-Fetal Medicine Unit, Department of Obstetrics and Gynaecology, University of Brescia Piazzale Spedali Civili,1, 25123 Brescia, Italy (e-mail: [email protected]) Accepted: 1 March 2013 TVol method has comparable sensitivity but higher specificity than the Hadlockmethod in predicting neonatal macrosomia

Detecting biophysical and geometrical characteristics of the canopy of three olive cultivars in hedgerow planting systems using an UAV and VIS-NIR cameras

The success of olive (Olea europaea) orchards depends on the interaction between genotype, planting system and orchard management. Research efforts often collide with the lack of high-throughput monitoring technologies for effective and rapid evaluation of expressed phenotypes under field conditions. Rapid phenotyping technologies allow to acquire a large amount of information in a relatively short period, optimizing efforts and labor. In an experiment carried out in Sicily, an unmanned aerial vehicle (UAV) equipped with VIS-NIR cameras was used to monitor canopy characteristics of three olive cultivars (‘Koroneiki’, ‘Biancolilla’ and ‘Calatina’), planted at three different planting distances (PD) (4×4, 4×3 and 4×2 m). Vegetative indices and canopy geometrical characteristics were calculated by means of the map algebra technique and structure from motion technique, respectively. Significant differences in the normalized differential vegetation index (NDVI) and green normalized differential vegetation index (GNDVI) values were measured for the different combinations of cultivars and PD. In particular, the highest and lowest values of NDVI and GNDVI indices were measured in Koroneiki (4×4 m) and ‘Calatina’ (4×3 m) plots, respectively. There was a linear relation between NDVI and pruning removed, expressed on both mass and volume per tree, for all cultivar × PD combinations. Tree canopy volume, estimated by the UAV-VIS camera technique, was higher in Koroneiki than in ‘Calatina’, with intermediate values measured in ‘Biancolilla’. The more spaced trees (4×4 m) had bigger canopies (6.4 m3) than those planted at 4×2 m (5.7 m3), but when the volume was expressed as m3 of canopy per m2 of soil the opposite trend was observed. The higher canopy volume per square meter was related to a higher fraction of intercepted PAR measured at noon. Our results indicate potential application of the UAV-VIS-NIR technique to determine canopy characteristics of different planting systems and cultivars of olive

‘Really Useful Research’ for real equality and justice in adult and community education

In recent decades, adult and community education has emerged as a distinctive discipline in its own right, based on scholarship in the quest for real equality and social justice. This distinctive discipline is already characterised by ‘really useful practice’, that is, critical, creative pedagogy, heavily influenced by women’s studies and women’s community education. Further, it draws on ‘really useful knowledge’, the cocreation of knowledge for critical consciousness. I make the case that we in the field need to develop a distinctive research approach to underpin the discipline, ‘really useful research’ that is dedicated to promoting emancipation, addressing inequality and inequity, in order to counter the ways in which research has been employed in maintaining the status quo. The article argues that research is not neutral, as feminist research approaches has demonstrated so clearly. And research has been used in a reductionist and instrumental manner, to implement global agendas for private gain rather than public good. Critical adult and community educators are dedicated to real equality and social justice, and ‘really useful research’ will provide the wherewithal to works towards that end