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The behavior of the Brazilian equatorial ionosphere during the solar minimum periods, 1996 and 2009, which cover the solar cycles 22/23 and 23/24, respectively, is investigated. For this, the F2 layer critical frequency (foF2) and peak height (hmF2) registered by a Digisonde operated at São Luis (2.33° S; 44° W) are carefully analyzed. The results show that the seasonal mean values of the foF2 and the hmF2 in the equinoxes and winter during 2009 were lower than in 1996. In the summer, an anomalous response to solar variability was observed. In this case, the hmF2 in 2009 is higher than in 1996 during a specific daytime interval. Besides that, it was verified that the prereversal enhancement of the zonal electric field (PRE) during the equinoxes in 2009 occurred a few minutes earlier than in 1996. Additionally, a Fast Fourier Transform (FFT) analysis was used to investigate the impacts of solar atmospheric tides (amplitude, diurnal, semidiurnal, and terdiurnal modes) on foF2 and hmF2 parameters with respect to its seasonality. Significant differences were observed between their values during the two minima, mainly in the amplitude of hmF2, which was higher in 1996 than in 2009 for all days analyzed. Moreover, the seasonality in the diurnal and semidiurnal modes for both periods presented an annual variability, while the terdiurnal mode exhibited annual and semiannual components. The results are compared with the International Reference Ionosphere (IRI) model, and the main differences between the observation and the model results are discussed in this work.

Burkina Faso relies on its substantial bovine population for meat and milk production, ensuring food security. The country hosts three primary taurine cattle populations: Lobi, Gourounsi Nahouri, and Gourounsi Ténado. These cattle are adapted to local conditions and exhibit valuable trypan tolerant traits, playing a crucial role in sustaining local communities and holding cultural and socioeconomic significance. This study aimed to assess the genetic diversity and structure of Burkina's primary taurine cattle populations using 27 microsatellite markers. Blood samples from 143 cattle representing these populations were genotyped. The analysis included assessing genetic diversity, deviations from Hardy-Weinberg equilibrium, calculating genetic distances, and population structure. The results revealed that all loci were polymorphic, indicating high allelic diversity. The overall mean FIS was moderate (0.028), ranging from -0.36 (CSRM60) to 0.73 (INRA035). Genetic differentiation between populations was moderate, accounting for 4% of the total differences. The highest pairwise FST was observed between Lobi and Gourounsi Ténado. The neighbor-joining tree displayed high admixture levels between Gourounsi populations, while Lobi cattle clustered as a distinct population. The population structure analysis indicated significant zebu gene introgression in Burkina taurine populations with relatively higher levels of admixtures in Gourounsi cattle compared to Lobi. The study provided a thorough genetic analysis of Burkina Faso's taurine cattle populations, uncovering the diversity and population structure. The study also revealed the differences in the prevalence of tsetse flies and associated trypanosomosis across the native tracts of Burkinabe taurine cattle populations had shaped the level of zebu introgression in them. [ABSTRACT FROM AUTHOR]

We investigated the association between 157 SNPs located in 75 candidate genes involved in the immune system and proxy traits for resistance to gastrointestinal nematodes in sheep. A total of 211 lambs from eight flocks were sampled. Nematode eggs per gram were counted and classified as: (i) Strongyles, (ii) Nematodirus spp., (iii) Trichuris spp. and (iv) Marshallagia marshalli. Single‐ and multiple‐locus models were used to test the marker–trait associations. Seven significant SNPs were identified on chromosomes OAR6, 15, 16, and 19. These findings provide insights for breeding nemarode‐resistant traits in low‐input production systems. General linear model, fixed and random model circulating probability unification, and Bayesian‐information and linkage‐disequilibrium iteratively nested keyway analyses identified a significant association between the eggs per gram of Strongyles nematodes and a specific variant of the PRLR gene. [ABSTRACT FROM AUTHOR]

In this paper we present details of the construction of a wideband, cryogenic receiver and its successful commissioning on the Arecibo Observatory 12 m telescope. The cryogenic receiver works in the 2.5–14 GHz frequency range. We upgraded the current narrow band, room temperature receivers of the telescope with the new wideband receiver. The current receiver is built around a Quadruple‐Ridged Flared Horn (QRFH) developed by Akgiray et al. (2013, https://doi.org/10.1109/tap.2012.2229953). To mitigate strong radio frequency interference (RFI) below 2.7 GHz, we installed a highpass filter before the first stage low noise amplifier (LNA). The QRFH, highpass filter, noise coupler and LNA are located inside a cryostat and are cooled to 15 K. The measured receiver temperature is 25 K (median value) over 2.5–14 GHz. The system temperature measured at zenith is about 40 K near 3.1 and 8.6 GHz and the zenith antenna gains are 0.025 and 0.018 K/Jy at the two frequencies respectively. We recommend the following improvements to the telescope system: (a) Upgrade the highpass filter to achieve better RFI rejection near 2.5 GHz; (b) Improve aperture efficiency at 8.6 GHz; (c) Upgrade the intermediate frequency system to increase the upper frequency of operation from 12 to 14 GHz. Key Points: Successful commissioning of a wideband, cryogenic receiver for the 12 m telescope at the Arecibo ObservatoryAchieved system temperature of 40 K and gains of 0.025 K/Jy and 0.018 K/Jy at frequencies 3.1 and 8.6 GHz respectively [ABSTRACT FROM AUTHOR]

The polyethylene-based matrix composites were facilitated in various engineering applications for good mechanical stability, dynamic load stability, and superior wear resistance. High-density polyethylene (HDPE) composites are gathering significance in agricultural and biomedical machinery applications. Due to stress cracking during high tensile load, it was limited. This investigation is an attempt to increase the tensile, flexural, and impact strength and wear behaviour of HDPE composites with inclusions of 0, 5, 10, and 15 vol% aluminas (Al2O3f) and constant 5 vol% of titanium oxide (TiO2f) bio-ceramic fillers through magnetic wave assisted injection mould technique. The influences of ceramic filler on HDPE composite's tensile, flexural, and impact strength were studied by ASTM D638, D790, and D256, respectively. ASTM G99 standard is used for estimating the wear resistance of composite by 10, 15, 20, 25 and 30N average load at 0.75 m/sec sliding velocity. The investigation outcome result of sample 4 offering high tensile, impact, and flexural strength 17.29 ± 1.98 MPa, 16.01 ± 0.13 kJ/m2, and 41.61 ± 1.56 MPa, respectively. The higher wear resistance with a low wear rate of (less than) 10 µm was found in sample 4. [ABSTRACT FROM AUTHOR]

The behavior of the Brazilian equatorial ionosphere during the solar minimum periods, 1996 and 2009, which cover the solar cycles 22/23 and 23/24, respectively, is investigated. For this, the F2 layer critical frequency (foF2) and peak height (hmF2) registered by a Digisonde operated at São Luis (2.33° S; 44° W) are carefully analyzed. The results show that the seasonal mean values of the foF2 and the hmF2 in the equinoxes and winter during 2009 were lower than in 1996. In the summer, an anomalous response to solar variability was observed. In this case, the hmF2 in 2009 is higher than in 1996 during a specific daytime interval. Besides that, it was verified that the prereversal enhancement of the zonal electric field (PRE) during the equinoxes in 2009 occurred a few minutes earlier than in 1996. Additionally, a Fast Fourier Transform (FFT) analysis was used to investigate the impacts of solar atmospheric tides (amplitude, diurnal, semidiurnal, and terdiurnal modes) on foF2 and hmF2 parameters with respect to its seasonality. Significant differences were observed between their values during the two minima, mainly in the amplitude of hmF2, which was higher in 1996 than in 2009 for all days analyzed. Moreover, the seasonality in the diurnal and semidiurnal modes for both periods presented an annual variability, while the terdiurnal mode exhibited annual and semiannual components. The results are compared with the International Reference Ionosphere (IRI) model, and the main differences between the observation and the model results are discussed in this work. [ABSTRACT FROM AUTHOR]

As the world grapples with the escalating threat of global warming, exploring sustainable agricultural practices has become imperative. Carbon sequestration is one such efficient method to mitigate carbon emissions and reduce global warming. Among the numerous sequestration options, terrestrial methods, notably via horticultural crops, have enormous potential. Horticultural crops, which encompass a diverse array of fruits, vegetables, plantations, and ornamental plants, offer a unique chance to sequester a considerable amount of atmospheric carbon dioxide. In particular, perennial horticultural systems provide numerous benefits over annual crops, such as increased productivity, reduced water and input requirements, and higher economic returns via carbon credits. However, the transition from annual to perennial crops presents logistical and financial challenges. The carbon sequestration capacity of plantations and horticulture crops is larger, at 16.4 Gt C, compared to the agroforestry system, which is at 6.3 Gt C. In order to fully use this capacity, it is essential to employ effective carbon management systems. These methods include growing higher biomass, recycling agricultural waste, employing animal manure, switching to perennial crops, adopting crop rotation, and encouraging agroforestry systems. Although there are advantages, substantial initial investments and continuous management are required to ensure effectiveness, and these demands might hinder widespread acceptance. This review emphasizes the critical role of horticulture systems in improving soil carbon levels, soil organic matter dynamics, different forms of carbon, and their overall potential for carbon sequestration. By unlocking the potential of horticultural crops to sequester carbon, we can help minimize atmospheric carbon dioxide levels, lessen the impact of climate change, and ensure nutritional security and economic benefits.