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Irrigation plays a vital role in sustaining agricultural production during periods of low rainfall. While ensuring increased productivity and economic profitability, irrigation is associated with high electrical energy consumption. In 2018, Brazilian Decree 9642 eliminated discounts for rural consumers, established in 2013. Leveraging renewable energy sources for irrigation can mitigate nonrenewable energy dependence and reduce the electricity costs for irrigators. This study aimed to nationally compare the economic viability of on-grid photovoltaic systems as an alternative to conventional grid energy for agricultural irrigation, both pre- and post-Brazilian Decree 9642. We conducted a comprehensive life cycle cost (LCC) analysis for both systems before and after discount termination, facilitating more informed economic decisions. The LCC of the conventional grid energy increased by over 40% after the Decree, whereas the photovoltaic system saw a modest increase of 12%. The solar system's 28% cost advantage over the conventional grid post-Decree underscores its resilience to regulatory changes. The photovoltaic system demonstrated viability when its LCC was equal to or lower than the comparator system's LCC. Notably, the economic viability of the photovoltaic system extended across all geographic regions for the grid-connected system. This study highlights the competitive pricing, versatility, and economic impact of photovoltaic systems in the context of changes in Brazilian tariff legislation. [ABSTRACT FROM AUTHOR]

Key message: Nitrate uptake in sugarcane roots is regulated at the transcriptional and posttranscriptional levels based on the physiological status of the plant and is likely a determinant mechanism for discrimination against nitrate. Sugarcane (Saccharum spp.) is one of the most suitable energy crops for biofuel feedstock, but the reduced recovery of nitrogen (N) fertilizer by sugarcane roots increases the crop carbon footprint. The low nitrogen use efficiency (NUE) of sugarcane has been associated with the significantly low nitrate uptake, which limits the utilization of the large amount of nitrate available in agricultural soils. To understand the regulation of nitrate uptake in sugarcane roots, we identified the major canonical nitrate transporter genes (NRTs—NITRATE TRANSPORTERS) and then determined their expression profiles in roots under contrasting N conditions. Correlation of gene expression with 15N-nitrate uptake revealed that under N deprivation or inorganic N (ammonium or nitrate) supply in N-sufficient roots, the regulation of ScNRT2.1 and ScNRT3.1 expression is the predominant mechanism for the modulation of the activity of the nitrate high-affinity transport system. Conversely, in N-deficient roots, the induction of ScNRT2.1 and ScNRT3.1 transcription is not correlated with the marked repression of nitrate uptake in response to nitrate resupply or high N provision, which suggested the existence of a posttranscriptional regulatory mechanism. Our findings suggested that high-affinity nitrate uptake is regulated at the transcriptional and presumably at the posttranscriptional levels based on the physiological N status and that the regulation of NRT2.1 and NRT3.1 activity is likely a determinant mechanism for the discrimination against nitrate uptake observed in sugarcane roots, which contributes to the low NUE in this crop species. [ABSTRACT FROM AUTHOR]

The low uptake of nitrogen (N) by sugarcane causes reduction in productivity and technological quality of sugarcane. Molybdenum (Mo) is a nutrient directly related to the assimilation of N. The objective of this study was to evaluate the effect of Mo and N on nitrate reductase activity (NRA), productivity and technological quality of sugarcane in ratoon cane cycle under Mo and N fertilization. A field experiment was carried out using the variety SP 933,094, subjected to four doses of Mo (0, 100, 200 and 400 g ha−1) and three doses of N (0, 60 and 120 kg ha−1). Biometric growth variables, NRA, productivity and technological quality of the sugarcane were evaluated. NRA increased with the application of Mo doses at all N levels, with a maximum of 400 g ha−1. The increase in the agricultural productivity was higher with N application of 120 kg ha−1, equal to 17 Mg ha−1 with Mo application of 206 g ha−1. The maximum increments in sugar productivity caused by Mo application were 12%, 27% and 18%, respectively, with N doses of 0, 60 and 120 kg ha−1. The combined doses of 120 kg ha−1 of N and 200 g ha−1 of Mo promoted greater agricultural productivity and sugar productivity. Our results suggest that Mo did not promote reduction in the use of N, but showed that nitrogen fertilization was stimulated by the use of Mo, by the increase in NRA, increasing the productivity and technological quality of sugarcane. [ABSTRACT FROM AUTHOR]

Localized solutions of an inhomogeneous cigar-shaped superfluid fermion gas are obtained in this paper. The effective mean field equation governing the cigar-shaped inhomogeneous superfluid Fermi gas is a nonlinear Schrödinger equation with variable coefficients. It is employed the similarity transformation method to convert the nonautonomous equation into an autonomous one. Furthermore, it is shown that the solution found for the autonomous equation is linearly stable. Finally, by using the conditional relations of the similarity transformation, the solution of the inhomogeneous system is constructed. Additional numerical simulations were performed to verify the stability of the solutions. [ABSTRACT FROM AUTHOR]

Building change detection techniques are essential for several urban applications. In this context, multi-temporal airborne LiDAR data has been considered an effective alternative since it has some advantages over conventional photogrammetry. Despite several works in the literature, the automatic class definition with great accuracy and performance remains a challenge in change detection. The developed strategies usually explore training samples or empirical thresholds to discriminate the classes. To overcome this limitation, we proposed an automatic building change detection method based on Otsu algorithm and median planarity attribute computed from eigenvalues. The main contribution corresponds to the automatic and unsupervised identification of building changes. The experiments were conducted using airborne LiDAR data from two epochs: 2012 and 2014. From qualitative and quantitative analysis, the robustness of the proposed method in detecting building changes in urban areas was evaluated, presenting completeness and correctness around 99% and 76%, respectively. [ABSTRACT FROM AUTHOR]

Aboveground biomass and nutrient accumulation differ among varieties of sugarcane (Saccharum spp. hybrids) throughout the crop development. This study aimed to identify irrigated sugarcane varieties with similar pattern of aboveground biomass production and nutrient extraction using cluster analysis and to determine the nutritional requirement during the plant cane cycle. Aboveground biomass production and nutrient content (N, P, K, Ca, and Mg) of sugarcane varieties (SP79-1011, RB813804, RB863129, RB872552, RB94336, RB72454, RB763710, SP78-4764, SP81-3250, RB867515, and RB92579) were determined at 120, 180, 240, 300, and 360 days after planting (DAP). Sugarcane varieties were clustered using the Ward's method based on aboveground biomass and nutrient accumulation. Next, the increase in aboveground biomass per month and nutritional requirement were determined for the varieties clusters. The sugarcane varieties were clustered in five groups: G1: RB92579; G2: RB863129 and SP81-3250; G3: SP78-4764 and RB867515; G4: SP79-1011; and G5: RB872552, RB813804; RB763710, RB72454, and RB943365. The RB92579 (G1) produced the highest aboveground biomass accumulation, corresponding to an average of 23 Mg ha−1 higher than the other varieties. The SP79-1011 (G4) exhibited constant aboveground biomass production in the last phase. The highest nutritional demand was observed for most of the varieties at the beginning of the stalk elongation phase (120 DAP), except for SP78-4764 and RB867515 (G3), which showed at beginning of the tillering phase (30 DAP). The nutritional requirements decreased during the final stage of stalks elongation phase. These findings suggest that nutritional management of sugarcane must consider the variety and growth phase. [ABSTRACT FROM AUTHOR]

Molybdenum (Mo) can stimulate nitrogenase activity (NTA), increase biological nitrogen (N) fixation (BNF) and reduce natural-abundance N isotopes (δ15N). Our hypothesis is that this stimulus depends on genotype and N availability for sugarcane. The objective of this study was to evaluate the effect of the Mo fertilization on BNF, NTA, δ15N and the accumulation of N in different genotypes (RB867515 and RB92579) of sugarcane fertilized with N. The cultivars were subjected to two rates of N fertilization (without N fertilization and 60 kg ha−1) and two rates of Mo fertilization (without Mo fertilization and 200 g ha−1). NTA, δ15N and BNF were evaluated throughout the cycle of the sugarcane. Both leaf and root NTA was maximal at approximately 100 DAP. Mo fertilization stimulated NTA in RB867515 but reduced in RB92579. The bacteria associated with the sugarcane fixed atmospheric-N2 and the Mo fertilization stimulated this fixation, especially without N fertilization. Mo fertilization promoted greater N accumulation and should be encouraged for fertility management, especially in soils with low N content or as an alternative for reducing the use of N fertilizers in sugarcane. [ABSTRACT FROM AUTHOR]

We study the non-negative solution u=u(x,t) to the Cauchy problem for the parabolic equation ∂tu=Δu+ξu on Zd×[0,∞) with initial data u(x,0)=10(x). Here Δ is the discrete Laplacian on Zd and ξ=(ξ(z))z∈Zd is an i.i.d. random field with doubly-exponential upper tails. We prove that, for large t and with large probability, most of the total mass U(t):=∑xu(x,t) of the solution resides in a bounded neighborhood of a site Zt that achieves an optimal compromise between the local Dirichlet eigenvalue of the Anderson Hamiltonian Δ+ξ and the distance to the origin. The processes t↦Zt and t↦1tlogU(t) are shown to converge in distribution under suitable scaling of space and time. Aging results for Zt, as well as for the solution to the parabolic problem, are also established. The proof uses the characterization of eigenvalue order statistics for Δ+ξ in large sets recently proved by the first two authors. [ABSTRACT FROM AUTHOR]

Military families are faced with specific challenges associated with the professional military context, such as the separation of the military member from the rest of the family, because of participation in international missions. This exploratory, qualitative study investigates the association between participation in such missions-before, during and after deployment-and marital relationships and parenting in Portuguese military families. A thematic analysis of interviews with 13 military's spouses indicates that in the pre-deployment phase children are prepared for the physical absence of the military parent, as emphasis is placed on clear communication that promotes the parent-child relationship. Some days before separation, the couple become closer and more intimate, enjoying their last moments alone. During deployment, the main challenges are the additional parental tasks and responsibilities of the parent who stays at home, insecurity regarding the marital relationship and a common concern for the deployed partner's well-being. On the other hand, the absence of the military parent may provide an opportunity for both the parent-child and couple relationships to be strengthened. During this phase the main resources used are communication technologies, which enable the absent parent/partner to be present psychologically and emotionally, as well as social support and personal resources/strengths. In the post-deployment phase, reintegration of the military member presents itself as a challenge to the family structure, and reorganization of parental responsibilities and roles is required. The couple also need to work on reestablishing intimacy. Despite some limitations which warrant attention, these results have important implications for research, given the lack of studies in this area in Portugal, and for clinical practice, since they offer pertinent clues regarding prevention and intervention within this type of family. [ABSTRACT FROM AUTHOR]

One of the drawbacks during second-generation biofuel production from plant lignocellulosic biomass is the accumulation of glucose, the preferred carbon source of microorganisms, which causes the repression of hydrolytic enzyme secretion by industrially relevant filamentous fungi. Glucose sensing, subsequent transport and cellular signalling pathways have been barely elucidated in these organisms. This study therefore characterized the transcriptional response of the filamentous fungus Aspergillus nidulans to the presence of high and low glucose concentrations under continuous chemostat cultivation with the aim to identify novel factors involved in glucose sensing and signalling. Several transcription factor- and transporter-encoding genes were identified as being differentially regulated, including the previously characterized glucose and xylose transporter HxtB. HxtB was confirmed to be a low affinity glucose transporter, localizing to the plasma membrane under low- and high-glucose conditions. Furthermore, HxtB was shown to be involved in conidiation-related processes and may play a role in downstream glucose signalling. A gene predicted to encode the protein kinase PskA was also identified as being important for glucose metabolism. This study identified several proteins with predicted roles in glucose metabolic processes and provides a foundation for further investigation into the response of biotechnologically important filamentous fungi to glucose. [ABSTRACT FROM AUTHOR]