Search Results (1,310)

The research results of soil penetration resistance (SPR) tests carried out on sandy clay using four cone probes with different dimensions of the measuring tip are presented in this study. It was indicated that the values of SPR can be used to diagnose the cultivation layer and, on this basis, determine whether it is necessary to cultivate it and select tools for the required treatment. Tests were carried out on three levels of soil density, 1.37, 1.43 and 1.51 g∙cm⁻³, and two moisture contents, 7.64% and 10.4%. The results show that the probe with the smallest cone with apex angles of 30° and 60° on the least dense soil indicated higher SPR by over 50% more than other probes with the highest cone and the same opening angles. The change in cone opening angle from 30° to 60° led to an increase in probe indications in the range of 10–25%, depending on the diameter of the cone tip. The statistical analysis shows that values of probe indications were statistically significant and were influenced by soil density, probe cone tip dimensions, the surface of the base and the apex angle. The values of SPR are fundamental in diagnosing the quality of the soil’s top layer, determining the necessity of breaking it up, and selecting the optimal tools for this procedure. To improve the efficiency of agricultural crop cultivation technologies. This is particularly important when carrying out cultivation procedures in an environmentally friendly manner. The measurements will help support the introduction of sustainable farming practices, including direct seeding, no-till cultivation, or precision agriculture, reducing soil degradation and increasing environmental benefits. Full article

Understanding the soil bacterial communities involved in carbon (C) and nitrogen (N) cycling can inform beneficial tillage and crop rotation practices for sustainability and crop production. This study evaluated soil bacterial diversity, compositional structure, and functions associated with C-N cycling at two soil depths (0–15 cm and 15–30 cm) under long-term tillage (conventional tillage [CT] and no-till [NT]) and crop rotation (monocultures of corn, soybean, and wheat and corn–soybean–wheat rotation) systems. The soil microbial communities were characterized by metabarcoding the 16S rRNA gene V4–V5 regions using Illumina MiSeq. The results showed that long-term NT reduced the soil bacterial diversity at 15–30 cm compared to CT, while no significant differences were found at 0–15 cm. The bacterial communities differed significantly at the two soil depths under NT but not under CT. Notably, over 70% of the tillage-responding KEGG orthologs (KOs) associated with C fixation (primarily in the reductive citric acid cycle) were more abundant under NT than under CT at both depths. The tillage practices significantly affected bacteria involved in biological nitrogen (N₂) fixation at the 0–15 cm soil depth, as well as bacteria involved in denitrification at both soil depths. The crop type and rotation regimes had limited effects on bacterial diversity and structure but significantly affected specific C-N-cycling genes. For instance, three KOs associated with the Calvin–Benson cycle for C fixation and four KOs related to various N-cycling processes were more abundant in the soil of wheat than in that of corn or soybean. These findings indicate that the long-term tillage practices had a greater influence than crop rotation on the soil bacterial communities, particularly in the C- and N-cycling processes. Integrated management practices that consider the combined effects of tillage, crop rotation, and crop types on soil bacterial functional groups are essential for sustainable agriculture. Full article

The future of humanity depends on successfully adapting key cropping systems for food security, such as corn (Zea mays L.), to global climatic changes, including changing air temperatures. We monitored the effects of climate change on harvested yields using long-term research plots that were established in 2001 near Fort Collins, Colorado, and long-term average yields in the region (county). We found that the average temperature for the growing period of the irrigated corn (May to September) has increased at a rate of 0.023 °C yr⁻¹, going from 16.5 °C in 1900 to 19.2 °C in 2019 (p < 0.001), but precipitation did not change (p = 0.897). Average minimum (p < 0.001) temperatures were positive predictors of yields. This response to temperature depended on N fertilizer rates, with the greatest response at intermediate fertilizer rates. Maximum (p < 0.05) temperatures and growing degree days (GDD; p < 0.01) were also positive predictors of yields. We propose that the yield increases with higher temperatures observed here are likely only applicable to irrigated corn and that irrigation is a good climate change mitigation and adaptation practice. However, since pan evaporation significantly increased from 1949 to 2019 (p < 0.001), the region’s dryland corn yields are expected to decrease in the future from heat and water stress associated with increasing temperatures and no increases in precipitation. This study shows that increases in GDD and the minimum temperatures that are contributing to a changing climate in the area are important parameters that are contributing to higher yields in irrigated systems in this region. Full article

The combination of no-till farming and green manure is key to nourishing the soil and increasing crop yields. However, it remains unclear how to enhance the efficiency of green manure under no-till conditions. We conducted a two-factor field trial of silage maize rotated with hairy vetch to test the effects of tillage methods and returning. Factor 1 is the type of tillage, which is divided into conventional ploughing and no-tillage; factor 2 is the different ways of returning hairy vetch as green manure, which were also compared: no return (NM), stubble return (H), mulching (HM), turnover (HR, for CT only), and live coverage (LM, for NT only). Our findings indicate that different methods of returning hairy vetch to the field will improve maize yield and quality. The best results were obtained in CT and NT in HM and LM, respectively. Specifically, HM resulted in the highest dry matter quality and yield, with improvements of 35.4% and 31.9% over NM under CT, respectively. It also demonstrated the best economic and net energy performance. However, other treatments had no significant effect on the beneficial utilization and return of nutrients. The LM improved yields under NT by boosting soil enzyme activity, promoting nitrogen transformation and accumulation, and increasing nitrogen use efficiency for better kernel development. Overall, NTLM is best at utilizing and distributing soil nutrients and increasing silage maize yield. This finding supports the eco-efficient cultivation approach in silage maize production in the region. Full article

With the increasing need for rare-earth elements (REEs) to reach the goals of the ongoing green energy transition, new and innovative methods are needed to identify new primary resources of these critical metals. This study explores the potential to use a non-biased, uniform till dataset to generate evidentiary layers that describe these critical factors and geochemical anomalies to aid mineral potential mapping (MPM) for REEs using machine-assisted methods. The till samples used in this study were collected from the “REE Line”, a sub-region within the Bergslagen lithotectonic province, Sweden, where numerous REE mineralizations occur. Multiple approaches were used in this study to isolate geochemical anomalies using multivariate methods, namely principal component analysis (PCA) and K-means clustering. Additional factors for classifying till samples were also tested, including alteration indices. Using known REE occurrences in Bergslagen as validation points, the results demonstrated the usefulness of multivariate methods applied to till geochemistry for predictive bedrock mapping, and to identify potential areas of REE mineralization within the REE line. The results of the alteration indices showed that the till geochemistry demonstrated similar levels of alteration when compared to the underlying bedrock, allowing for a regional alteration map to be generated. These results show that regional-scale till sampling can provide low-cost data for mineral exploration at the regional scale and generate usable evidentiary layers for GIS-based MPM. Full article

In no-till cropping systems, banding of phosphorus (P) fertiliser at seeding results in low use efficiency due to chemical reactions in soil. Foliar P has the potential to allow grain producers to respond tactically with P application after sowing when P supply from soil and fertiliser is not meeting crop demand. The objective of this study was to evaluate the effectiveness of foliar P on wheat grain yield, grain quality, biomass yield, P uptake and P use efficiency indices. Nine field experiments were conducted to investigate the response of wheat to foliar P. Three rates of P, 0, 2.5 and 5.0 kg/ha, as phosphoric acid (H₃PO₄ 85%) were applied to wheat at three different growth stages: first tiller emergence (Z21), first node detection (Z31) and flag leaf emergence (Z39). Grain yield responses ranging from 176 kg/ha to 505 kg/ha to foliar-applied P were observed in six out of nine experiments. The percent grain yield response to foliar P was negatively related to the P buffering index (PBI, 0–10 cm soil depth), which is attributed to greater sorption by soil of the foliar P at the higher PBI levels. Mean agronomic efficiency (AE) across the experiments was 111 kg/kg P but reached up to 232 kg/kg P. It was also evident that foliar P has the potential to improve P concentration in shoots and grains and increase P uptake but with no or minimal effect on grain quality. Our results suggest that a combination of tissue testing at the seedling stage and soil P buffering can be used to guide when foliar P application is likely to increase grain yield in wheat. Full article

Despite being very old, the mining industry continues to be one of the major sources of pollution, with more people killed or injured than in all other industries. Prevention of incidents/accidents on machinery in mining pits and the issues of operator safety on mining machinery largely depend on the ergonomic adaptation of the workplace, compliance with safety procedures and policies, and organizational and other influential factors. Evidently, scarce consideration of those factors in the available literature has not given satisfactory results till now. The aim of this paper is to first set up a comprehensive model based on ergonomic factors and contextual theory, which takes into account all the influencing factors on the occurrence of incidents/accidents and represents a complex system of interdependence of influential variables of diverse, mostly stochastic nature, and then design a software solution on the given basis. In this research, based on the extensive data collected, a model was generated using the structural equations modelling methodology, which was then used to design the reasoning logic in the expert system for mitigating the risks of the operation of mining machines. An innovative solution incorporating a mathematical model of the interdependence of influential variables into the stored knowledge base offers a decision support system that provides recommendations for the maintenance of a particular mining machine, depending on the assessment of model factors in a specific decision-making situation at the higher organizational level and ergonomic suitability for the operator at the lower organizational level, and, in that manner, enables the mitigating of risky/unwanted events. Full article

A decline in rainfall as a source of agricultural water has affected and will continue to affect sustainable crop production globally including in Hungary. Conservation of the greatest water reservoir is important for the sustainable development of agriculture in Hungary. The objective of this study was to evaluate the effects of the different tillage methods on soil moisture content, grain yield, and root weight of wheat (Triticum aestivum) and sunflower (Helianthus annuus) under rainfed conditions. A field study was conducted at the Józsefmajor Experimental and Training Farm (JM) of the Hungarian University of Agriculture and Life Sciences near Hatvan. The experiment consisted of six tillage treatments: disking (D, 16 cm), shallow cultivation (SC, 20 cm), no-till (NT), deep cultivation (DC, 25 cm), loosening (L, 45 cm), and plowing (P, 30 cm). Soil moisture content (SMC) was measured monthly, and grain yield and root weight were measured at the end of the cropping period. Our results showed no significant difference in SMC between conservation and conventional tillage methods in 2018. However, in 2021, greater SMC was significantly conserved under NT compared to P. Regarding the sampling date, a significant increase in moisture with time was observed. A significantly lower SMC was observed on 3 June 2019 between L and D. while on the 9 September 2020, SMC significantly differed between P and all the other treatments (D, SC, NT, DC, and L). Interestingly in 2018, SMC was significantly lower at 10–20 cm depth between L and D. Notably the effect of depth on SMC was observed as moisture significantly increased with increasing depth in all tillage treatments. Root weight was greatest at DC (1.54 t ha⁻¹) in 2018 and under L (3.89 t ha⁻¹) in 2021. Similarly, wheat grain yield was greatest at DC (2.48 t ha⁻¹) in 2018, while sunflower yield in 2021 was greatest at L (3.86 t ha⁻¹). It is comprehensible that conservation tillage methods such as L and NT can increase SMC and grain yield. Full article

To design a high-performance stubble-breaking device, studying the interaction mechanisms between blades and root–soil composites is urgent. A simplified experimental method was proposed to investigate the cutting process and the effects of key factors on cutting by conducting cutting experiments on remolded root–soil composites and maize root–soil composites. The results showed that the soil support force and root–soil interface force significantly impacted cutting. Higher soil compaction and root–soil interface forces helped avoid root dragging, but higher soil compaction and thicker roots led to greater resistance. The superposition and accumulation effects significantly increased the cutting force, especially when root distribution was denser; as the oblique angle and bevel angle increased, the root-cutting force and dragging distance first decreased and then increased. Compared with orthogonal cutting, the optimal angles were both 45° and reduced the root-cutting force by 60.47% and 15.12% and shortened the dragging distance by 22.33 mm and 8.76 mm, respectively. Increasing the slide-cutting angle and cutting speed helped reduce the root-cutting force and dragging distance; however, it also faced greater pure-cutting force. Consequently, the interaction mechanisms between blades and root–soil composites revealed in this study provide a design and optimization basis for stubble-breaking devices, thus promoting the development of no-till technology. Full article

A line-field confocal optical coherence tomography (LC-OCT) combines confocal microscopy and optical coherence tomography into a single, rapid, easy-to-use device. This meta-analysis was performed to determine the reliability of LC-OCT for diagnosing malignant skin tumors. PubMed, EMBASE, Web of Science databases, and the Cochrane Library were searched for research studies in the English language from inception till December 2023. To assess quality and the risk of bias, the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) was used. The sensitivity and specificity of each study were calculated. The bivariate summary sensitivity and specificity were calculated using the linear mixed model. Five studies with 904 reported per lesion analyses in our study; the specificity and sensitivity ranged from 67% to 97% and 72% to 92%, respectively. The pooled specificity and sensitivity were 91% (95% CI: 76–97%) and 86.9% (95% CI: 81.8–90.8%), respectively. The summary sensitivity and specificity from the bivariate approach are 86.9% (95% CI: 81.8–90.8%) and 91.1% (95% CI: 76.7–97.0%), respectively. The area under the curve is 0.914. LC-OCT shows great sensitivity and specificity in diagnosing malignant skin tumors. However, due to the limited number of studies included in our meta-analysis, it is premature to elucidate the true potential of LC-OCT. Full article

By improving soil properties, cover crops can reduce wind erosion and sand damage to emerging cotton (Gossypium hirsutum L.) plants. However, on the Texas High Plains, questions regarding cover crop water use and management factors that affect cotton lint yield are common and limit conservation adoption by regional producers. Studies were conducted near Lamesa, TX, USA, in 2017–2020 to evaluate cover crop species selection, seeding rate, and termination timing on cover crop biomass production and cotton yield in conventional and no-tillage systems. The no-till systems included two cover crop species, rye (Secale cereale L.) and wheat (Triticum aestivum L.) and were compared to a conventional tillage system. The cover crops were planted at two seeding rates, 34 and 68 kg ha⁻¹, and each plot was split into two termination timings: optimum, six to eight weeks prior to the planting of cotton, and late, which was two weeks after the optimum termination. Herbage mass was greater in the rye than the wheat cover crop in three of the four years tested, while the 68 kg ha⁻¹ seeding rate was greater than the low seeding rate in only one of four years for both rye and wheat. The later termination timing produced more herbage mass than the optimum in all four years. Treatments did not affect cotton plant populations and had a variable effect on yield. In general, cover crop biomass production did not reduce lint production compared to the conventional system. Full article

Background and aim: Candida infection is a significant cause of morbidity and mortality in neonatal intensive care units (NICU) globally. We aimed to conduct a systematic review to investigate the prevalence of candida among causative organisms of neonatal sepsis and identify the distribution of candida species infecting Saudi neonates. Methods: We comprehensively searched Web of Science, Scopus, PubMed, and Cochrane Library from their inception till November 2023. After screening titles, abstracts, and full texts, we ultimately included 21 eligible studies. The designs of the included studies were randomized clinical trials, cohorts, case–control, and case reports; the methodological quality was appraised using the Cochrane risk of bias assessment tool, NIH tool for observational studies, and Murad tool for assessing case reports. Results: Our systematic review and meta-analysis pooled data reported in 21 studies in the Saudi populations, which provided data on different types of candidal infections in 2346 neonates. The pooled data of ten retrospective studies enrolling 1823 neonates revealed that candida species resembled 4.2% of the causative organisms of neonatal sepsis among Saudi neonates (95%CI [2.5%; 5.9%], p = 0.000). Additionally, out of a total of 402 candida species that were identified among the included studies, C. albicans prevailed mostly among Saudi neonates, followed by C. parapsilosis, NS candida, and C. tropicalis (50.25%, 21.40%, 12.44%, and 9.45%, respectively). Conclusions: We found that candida species prevailed in 4.2% of 1823 cases of neonatal sepsis; the most common candida species was C. albicans. We could not pool data regarding risk factors or susceptibility of candida species to different treatment modalities due to insufficient data, requiring future large-scale, high-quality studies to be conducted. Full article

The development of dynamic plasticity models with accounting of interplay between several plasticity mechanisms is an urgent problem for the theoretical description of the complex dynamic loading of materials. Here, we consider dynamic plastic relaxation by means of the combined action of dislocations and phase transitions using Al-Cu solid solutions as the model materials and uniaxial compression as the model loading. We propose a simple and robust theoretical model combining molecular dynamics (MD) data, theoretical framework and machine learning (ML) methods. MD simulations of uniaxial compression of Al, Cu and Al-Cu solid solutions reveal a relaxation of shear stresses due to a combination of dislocation plasticity and phase transformations with a complete suppression of the dislocation activity for Cu concentrations in the range of 30–80%. In particular, pure Al reveals an almost complete phase transition from the FCC (face-centered cubic) to the BCC (body-centered cubic) structure at a pressure of about 36 GPa, while pure copper does not reveal it at least till 110 GPa. A theoretical model of stress relaxation is developed, taking into account the dislocation activity and phase transformations, and is applied for the description of the MD results of an Al-Cu solid solution. Arrhenius-type equations are employed to describe the rates of phase transformation. The Bayesian method is applied to identify the model parameters with fitting to MD results as the reference data. Two forward-propagation artificial neural networks (ANNs) trained by MD data for uniaxial compression and tension are used to approximate the single-valued functions being parts of constitutive relation, such as the equation of state (EOS), elastic (shear and bulk) moduli and the nucleation strain distance function describing dislocation nucleation. The developed theoretical model with machine learning can be further used for the simulation of a shock-wave structure in metastable Al-Cu solid solutions, and the developed method can be applied to other metallic systems, including high-entropy alloys. Full article

Cotton (Gossypium hirsutum) requires a long growing period for fruit and fiber maturation, making it vulnerable to insect pests, thus affecting the seed cotton yield and fiber quality. Cotton-feeding thrips (Thysanoptera: Thripidae) are one of the major insects impacting cotton yield throughout the U.S. cotton belt and worldwide. A two-year field research conducted at Texas A&M AgriLife Research farm in west Texas, USA quantified the interactive effect of three cover crops [wheat (Triticum aestivum), rye (Secale cereale), and no cover] and three irrigation regimes [rainfed, deficit irrigation (30%) and full irrigation] on thrips population dynamics across the phenologically susceptible stages of upland cotton and resulting impact on plant growth and yield parameters. Temporal densities of thrips, feeding injury from thrips, cotton growth and reproductive profiles, yield, and fiber quality varied with cover crops and irrigation levels. Thrips densities were conspicuously low due to harsh weather conditions, but the densities decreased with an increase in plant age. Terminated rye and wheat cover versus conventional-tilled, no-cover treatments showed marginal effects on thrips colonization and population dynamics. Similarly, full irrigation treatment supported higher thrips densities compared to rainfed and deficit irrigation treatments. Immature thrips densities increased through the successive sampling periods, indicating increased thrips reproduction following the initial colonization. Thrips feeding injury was significantly greater in no-cover plots in the early seedling stage, but the effect was insignificant across all cover crop treatments in subsequent sampling dates. The results of this study demonstrated increased seedling vigor, plant height, and flower densities in terminated cover crop plots across all irrigation regimes compared to that in no-cover plots. However, the cover crop x irrigation interaction significantly impacted the cotton lint yield, with increased lint yield on cover crop treatments. This study clearly demonstrates the value of cover crops in semi-arid agricultural production systems that are characterized by low rainfall, reduced irrigation capacity, and wind erosion of topsoil. Full article

Forage sorghum is an alternative source for biofuel feedstock production and may also provide forage for livestock operations. Introducing biofuel feedstock as a dual-use forage to livestock operations has the potential to increase the adoption of biofuel feedstock production. However, additional technical agronomic information focusing on tillage, row arrangement, and harvest date for forage sorghum planted into pasturelands intended for dual use is needed. Three tillage treatments, disking and rototilling (RT), chisel plow (CP), and no tillage (NT), and two row arrangement treatments, single-row planting with 76.2 cm rows and twin rows of 17.8 cm on 76.2 cm centers, were tested for effects on forage sorghum yield in a 3-cut system. This study tested two sites in Booneville, AR, from 2010 to 2012. Several interactions with year were detected, likely due to large precipitation differences within and among years. The year greatly affected the yield, with greater (p < 0.05) yields in year 1 compared to years 2 and 3 in both locations. No till resulted in lower yields in some years and harvest dates, though no clear trend was detected among tillage treatments over years. Twin rows generally did not improve yield, except for the third harvest date at one location. No strong trends for tillage or row arrangement effects were observed in this study. Inconsistencies may have resulted from the strong influence of year or interactions of multiple factors, which may challenge producers interested in utilizing forage sorghum for biofuels and livestock feed. Full article