Preliminary study on the potential use of RPA images to quantify the influence of the defoliation after coffee harvesting to its yield

Received: January 24th, 2023 ; Accepted: May 22nd, 2023 ; Published: September 18th, 2023 ; Correspondence: [email protected] is an agricultural commodity with global commercial importance capable of impacting the production chain. The quantification of defoliation at harvest is important for monitoring crop yield because defoliation is one of the main types of damage caused by this agricultural operation in coffee crops. Thus, the objective of this study was to evaluate the relationship between yield and defoliation obtained in the field and obtained through remotely piloted aircraft (RPA) images. The experiment was conducted in a coffee plantation belonging to the Federal University of Lavras (UFLA), Lavras, Minas Gerais state, Brazil. An RPA with a rotary wing containing a multispectral camera was used in autonomous flight mode with a height of 30 m, an image overlap of 80%, and a speed of 3 m s-1 . The images were collected before and after the 2020 and 2021 harvest, defoliation data obtained in the field were measured in 2020 and 2021, and the yield was measured from 2019 to 2021. Image processing was performed in the software PhotoScan, postimage processing was performed in QGIS, and statistical analyses were performed using the software R. With the processing of the images in 2020, the crop showed reductions of 17.3% and 18.4% in leaf area and volume, respectively, after harvest. In 2021, the crop showed reductions of 12.8% and 9.8% in leaf area and volume, respectively, after harvest. The leaf area and leaf volume of the coffee plantation after harvest could be quantified by means of images obtained by RPA, which allowed the observation of the loss of area and volume of the coffee plantation. Furthermore, it was possible to analyse the interactions between field data and the yield of the same harvest year, which were directly proportional, and the interaction of image data from one year with the previous yield, which were inversely proportional. In the year 2020, there was a reduction of 17.3% in leaf area after harvest, and a reduction of 18.4% in leaf volume after harvest in the plots under study.In the processing carried out in 2021, there was a 12.8% reduction in leaf area after harvest, and a 9.8% decrease in leaf volume after harvest in the plots under study

Antibiotic resistance genes detected in the marine sponge <i>Petromica citrina</i> from Brazilian coast

Although antibiotic-resistant pathogens pose a significant threat to human health, the environmental reservoirs of the resistance determinants are still poorly understood. This study reports the detection of resistance genes (ermB, mecA, mupA, qnrA, qnrB and tetL) to antibiotics among certain culturable and unculturable bacteria associated with the marine sponge Petromica citrina. The antimicrobial activities elicited by P. citrina and its associated bacteria are also described. The results indicate that the marine environment could play an important role in the development of antibiotic resistance and the dissemination of resistance genes among bacteria

Draft genome sequences of photobacterium damselae subsp. piscicida SNW-8.1 and PP3, two fish-isolated strains containing a type III secretion system

Here, we report the draft genome sequences of two strains of the fishpathogenPhotobacterium damselaesubsp.piscicida, isolated fromSalmo salar(SNW-8.1) andSeriola quinqueradiata(PP3). The identification of a type III secretion systemin the two genomes furthers our understanding of the pathobiology of this sub-speciesThis work has been supported by grant AGL2016-79738-R (AEI/FEDER, EU) from the Agencia Estatal de Investigación (AEI) of Spain and cofunded by the FEDER Program from the European Union. The support of Xunta de Galicia (Spain) with grant ED431C 2018/18 is also acknowledgedS

Magnetic and pair correlations of the Hubbard model with next-nearest-neighbor hopping

A combination of analytical approaches and quantum Monte Carlo simulations is used to study both magnetic and pairing correlations for a version of the Hubbard model that includes second-neighbor hopping $t^{\prime }=-0.35t$ as a model for high-temperature superconductors. Magnetic properties are analyzed using the Two-Particle Self-Consistent approach. The maximum in magnetic susceptibility as a function of doping appears both at finite $$ and at $t^{\prime }=0$ but for two totally different physical reasons. When $t^{\prime }=0$, it is induced by antiferromagnetic correlations while at $t^{\prime }=-0.35t$ it is a band structure effect amplified by interactions. Finally, pairing fluctuations are compared with $$-matrix results to disentangle the effects of van Hove singularity and of nesting on superconducting correlations. The addition of antiferromagnetic fluctuations increases slightly the $d$-wave superconducting correlations despite the presence of a van Hove singularity which tends to decrease them in the repulsive model. Some aspects of the phase diagram and some subtleties of finite-size scaling in Monte Carlo simulations, such as inverted finite-size dependence, are also discussed.Comment: Revtex, 8 pages + 15 uuencoded postcript figure

Análise geoambiental do riacho Santa Bárbara Zona urbana – Parnarama-Maranhão

Análise geoambiental do riacho Santa BárbaraZona urbana – Parnarama-Maranhã

Superconductivity in the Nb2SnC compound

Nb2SnC is a member of the large family of lamellar materials that crystallize in the hexagonal structure with space group P63/mmc which are isomorphs with Cr2AlC, also named H-phase. In spite of the great number of compounds which belong to this family, the superconductivity has been reported only for two cases: Mo2GaC and Nb2SC. In this work we show that superconductivity can be observed in Nb2SnC depending on the synthesis method used. The quality of the superconductor is strongly dependent of the synthesis method and the optimal results were reached for samples synthesized at 2.5 GPa and 523 +/- 50oC. This sample showed a critical temperature close to 7.8K, revealed from magnetization and transport measurement, the highest critical temperature reported up to now for an H-phase.Comment: paper with 12 pages and 4 figure

From cosmic deceleration to acceleration: new constraints from SN Ia and BAO/CMB

We use type Ia supernovae (SN Ia) data in combination with recent baryonic acoustic oscillations (BAO) and cosmic microwave background (CMB) observations to constrain a kink-like parametrization of the deceleration parameter ($q$). This $q$-parametrization can be written in terms of the initial ($q_i$) and present ($q_0$) values of the deceleration parameter, the redshift of the cosmic transition from deceleration to acceleration ($z_t$) and the redshift width of such transition ($\tau$). By assuming a flat space geometry, $q_i=1/2$ and adopting a likelihood approach to deal with the SN Ia data we obtain, at the 68% confidence level (C.L.), that: $z_t=0.56^{+0.13}_{-0.10}$, $\tau=0.47^{+0.16}_{-0.20}$ and $q_0=-0.31^{+0.11}_{-0.11}$ when we combine BAO/CMB observations with SN Ia data processed with the MLCS2k2 light-curve fitter. When in this combination we use the SALT2 fitter we get instead, at the same C.L.: $z_t=0.64^{+0.13}_{-0.07}$, $\tau=0.36^{+0.11}_{-0.17}$ and $q_0=-0.53^{+0.17}_{-0.13}$. Our results indicate, with a quite general and model independent approach, that MLCS2k2 favors Dvali-Gabadadze-Porrati-like cosmological models, while SALT2 favors $\Lambda$CDM-like ones. Progress in determining the transition redshift and/or the present value of the deceleration parameter depends crucially on solving the issue of the difference obtained when using these two light-curve fitters.Comment: 25 pages, 9 figure