Field Study Research Articles

Barley yellow dwarf virus in winter barley: Control in light of resistance issues and loss of neonicotinoid insecticides

AbstractBarley yellow dwarf virus (BYDV) is the most widespread viral disease of cereal crops vectored by aphids, causing stunting of the crop and significant yield loss. Management recommendations for autumn sown cereals has centred on the timely control of aphid vectors, particularly their management before the crop has reached Growth Stage 31 (stem elongation). In recent years two separate but related issues have emerged, (i) the detection of pyrethroid resistance in a single Sitobion avenae SA3 clone and (ii) the withdrawal of neonicotinoid insecticide seed dressing; widely used to manage aphids in the early development of cereal crops. A series of replicated field studies were conducted from 2016 to 2019 to ascertain if the pyrethroid insecticide is still effective in light of the SA3 clones' presence in aphid populations and if withdrawal of neonicotinoid seed dressings has negatively affected aphid management. Both disease levels and yields confirmed that the neonicotinoid, clothianidin, applied as a seed treatment significantly contributed to the management of BYDV in the different trials investigated. Results of this study demonstrate application of a foliar (lambda‐cyhalothrin or a sulfoxaflor) insecticide has a significant positive impact on yield. Foliar pyrethroid insecticides were as effective in protecting yield from BYDV as the neonicotinoid seed treatments. In the absence of neonicotinoid seed dressing, alternative insecticides still offer protection for winter barley crops against the aphid vectors of BYDV and associated yield loss. Furthermore, the presence of a pyrethroid resistant Sitobion avenae SA3 clone had no observable impact on field efficacy of the pyrethroid insecticide, lambda‐cyhalothrin in these trials. However, this needs continuous monitoring because of potential further increases in resistance levels or emergence of additional resistance mechanisms, which could render pyrethroid insecticides ineffective.

Calculation and Comparison of Step Guidelines for Preschooler Physical Activity While Indoors.

Preschooler physical activity (PA) is vital for growth and development. The World Health Organization PA guidelines state preschoolers should achieve ≥ 180 min/day of Total PA (TPA) of which ≥ 60 min is moderate-to-vigorous PA (MVPA). A step/day recommendation to match these guidelines may be a more practical metric for caregivers to promote PA. The purpose of our investigation is to improve upon existing step recommendations by creating one for indoor-based activities, acknowledging where preschoolers spend most of their time, and various cut-points for PA. In a laboratory study (Aim 1), a validated direct observation protocol was used to quantify preschooler PA intensity while performing indoor activities (n = 35). Actigraph GT3x accelerometers were placed on the waist, wrist, and ankle to measure step count. In a field study (Aim 2), habitual PA of 881 preschoolers (7113 valid days) via waist-worn accelerometers was used to assess the agreement between created guidelines (Aim 1) and other step recommendations with PA guidelines using Receiver Operating Characteristic and Area Under the Curve (ROC-AUC). In the laboratory study, calculated indoor step ranges were 6960-7440 (waist), 7200-8640 (wrist), and 7680-9120 (ankle) to align with existing PA guidance. In the field, the higher step guidelines (> 12 000) achieved very limited agreement, due to few preschoolers achieving this metric. The 6000 step/day guidelines had the highest agreement (AUCs: TPA: 0.637; MVPA: 0.751; TPA + MVPA: 0.761) with PA guideline. When preschoolers are indoors, 6000 steps may be the minimum for adequate PA.

РОЛЬ РЕГИОНАЛЬНЫХ ТЕКТОНИЧЕСКИХ НАПРЯЖЕНИЙ В ГРЯЗЕВОМ ВУЛКАНИЗМЕ ЮЖНОГО САХАЛИНА

The article is devoted to the study of the tectonic stress field of Southern Sakhalin on the basis of seismological, geological, tectonophysical, GPS and remote (satellite) methods. The most characteristic type of stress state for the South of Sakhalin is latitudinal — sublatitudinal horizontal compression. The field forming the morphology of the Pugachev and Yuzhno-Sakhalinsk mud volcanoes, as well as the shape of their lithoclastite fields, fully corresponds to the nature of this state, which is confirmed by the analysis of satellite images.The images were used to supplement the results of previous researchers on the study of the directions of the gryphon bands and to measure deformation of volcano lithoclastite fields. The Pugachev volcano lithoclastite fields bend strikes 25°, and that of the Yuzhno-Sakhalinsk mud volcano strikes 30°, which well corresponds to the regional tectonic stress field. The expediency of using remote (satellite) methods as an supplement to geological and geophysical methods, in particular borehole caliper, is shown.

Simulation of Gas‐Particle Partitioning of Semi‐Volatile n‐Alkanes and PAHs in Nanjing, China, and Denver, United States: Effects of Vapor Pressure and Surface Adsorption Estimation

AbstractThe concentration data of semi‐volatile n‐alkanes and PAHs in the gas phase and in PM2.5 were obtained from Nanjing and Denver. First, the gas‐particle partitioning coefficients of the target compounds were calculated and compared with the predictions based on the equilibrium absorptive partitioning theory. Although the vapor pressure (poL) estimation method was selected to improve the agreement between measured and predicted partitioning coefficients, n‐alkanes in Denver and PAHs in both cities exhibited stronger sorption to PM2.5 than predicted. By including the adsorption mechanism, the average logarithms and temporal variations of the partitioning coefficients were well simulated in both Nanjing and Denver. The partitioning of n‐alkanes in Nanjing can be primarily explained by the absorption mechanism, while the adsorption mechanism dominates that for n‐alkanes in Denver and PAHs in both cities. To obtain an optimal simulation, the poL of n‐alkanes and PAHs was estimated using the SPARC and SIMPOL—two group contribution methods, respectively, and the difference between desorption and vaporization enthalpies was set between 2 and 3 kcal mol−1 for n‐alkanes in Denver and PAHs in both cities. Therefore, the estimation of poL and surface adsorption should be carefully considered when parameterizing the gas‐particle partitioning of non‐polar organic compounds in future field and modeling studies.

Assessing the role of natural kelp forests in modifying seawater chemistry

Climate change is causing widespread impacts on seawater pH through ocean acidification (OA). Kelp forests, in some locations can buffer the effects of OA through photosynthesis. However, the factors influencing this variation remain poorly understood. To address this gap, we conducted a literature review and field deployments of pH and dissolved oxygen (DO) loggers within four habitats: intact kelp forest, moderate kelp cover, sparse kelp cover and barrens at one site in Port Phillip Bay, a wind-wave dominated coastal embayment in Victoria, Australia. Additionally, a wave logger was placed directly in front of the intact kelp forest and barrens habitats. Most studies reported that kelp increased seawater pH and DO during the day, compared to controls without kelp. This effect was more pronounced in densely populated forests, particularly in shallow, sheltered conditions. Our field study was broadly consistent with these observations, with intact kelp habitat having higher seawater pH than habitats with less kelp or barrens and higher seawater DO compared to barrens, particularly in the afternoon and during calmer wave conditions. Although kelp forests can provide local refuges to biota from OA, the benefits are variable through time and may be reduced by declines in kelp density and increased wave exposure.

Machine learning force field study of carboxylate ligands on the surface of zinc-blende CdSe quantum dots

Machine learning force field study of carboxylate ligands on the surface of zinc-blende CdSe quantum dots

Mathematical sense making of quantum phenomena using Dirac notation: its effect on secondary school students’ functional thinking about photons

Previous research has consistently demonstrated that students often possess an inadequate understanding of fundamental quantum optics concepts, even after formal instruction. Findings from physics education research suggest that introducing a mathematical formalism to describe quantum optical phenomena may enhance students’ conceptual understanding of quantum optics. This paper investigates whether using formal descriptions of quantum optics phenomena – such as photon anticorrelation at a beamsplitter or single-photon interference in a Michelson interferometer – expressed in Dirac notation, can support secondary school students in developing functional thinking about photons. To investigate this, we conducted a clusterrandomized field study, comparing the improvement in functional thinking between 67 students in the intervention group, who were taught using both qualitative and quantitative reasoning, and 66 students in the control group, who were taught using only qualitative reasoning. The results indicate that mathematical formalism can indeed promote functional thinking about photons. However, the comparison between the intervention and control groups revealed that the control group exhibited a greater increase in functional thinking than the intervention group. In response to these findings, we conducted a follow-up study aimed at gaining a deeper understanding of the cognitive load associated with both approaches. Specifically, we compared the intrinsic and extraneous cognitive load of 71 students in the intervention group with those of 65 students in the control group. The data analysis revealed that the two groups had statistically significant differences in intrinsic cognitive load while the extraneous cognitive load did not difer statistically significant, indicating a higher mental effort associated to the quantitative reasoning.

Insights from a 19-year field study: optimizing long-term nutrient supply strategies for enhanced crop productivity and nutritional security in rice–wheat systems

What nutrient supply options can ensure maximum productivity and optimize the nutrient uptake of rice–wheat system (R-W system)? an experiment started in the year 1998 (19-year-old) to examine the impact of optimal nutrient supply (NS) strategies to maximize crop productivity and nutritional security in R-W system. To determine the best nutrient management strategies (BNMS), seven different NS methods were tested. These included (organic and mineral fertilizers), as well as combinations such as integrated plant nutrition system (IPNS), IPNS + B (berseem), and IPNS + C (cowpea), with the aim of enhancing the productivity and nutrient absorption of R-W system. Results showed that rice grain yield notably wide-ranging from 1.61 to 5.81 t ha−1 under different NS options and highest rice grain yield (mean of 19 years) was observed at IPNS + C (5.81 t ha−1), which was at par with IPNS (5.79 t ha−1), STCR (soil test crop response) (5.76 t ha−1) and IPNS + B (5.67 t ha−1) followed by 100% recommended dose fertilizer NPK (4.41 t ha−1), which equality with OF (organic farming) (4.04 t ha−1) and lowest was recorded in control plot (1.61 t ha−1). Wheat grain yield varied significantly from 1.43 to 5.86 t ha−1 under different NS options. The highest yield (mean of 19 years) was observed in treatments IPNS + B (5.86 t ha−1), IPNS (5.77 t ha−1), IPNS + C (5.48 t ha−1), and STCR (5.45 t ha−1), followed by OF at 4.49 t ha−1, NPK at 3.76 t ha−1, with the lowest in the control plot at 1.43 t ha−1. Additionally, total phosphorus and sulfur accumulation in rice (grain: 8.41 to 39.09 kg ha−1; straw: 6.02 to 23.54 kg ha−1) varied significantly across nutrient supply treatments. Overall, adoption of IPNS integration with legumes (IPNS + B and IPNS + C), can significantly improve productivity and nutrient accumulation in R-W systems. Incorporating legumes into farming practices is advised for sustained productivity and nutritional benefits.

The fate of ultramafic-rich mélanges in cold to hot subduction zones: Implications for diapirism (or not) and chemical geodynamics

Buoyant ultramafic-rich (serpentine- or chlorite-rich) mélange diapirs in sediment-starved subduction zones can transport slab material to arc sources. While the buoyancy of chlorite-rich mélanges was previously investigated, serpentine-rich mélanges were never explored. Thus, the overall contribution of ultramafic-rich mélanges to buoyancy, the conditions for diapir formation, and their fate in subduction zones are not well constrained. Here, we investigate the partial melting behavior and the associated density transformations of a serpentine-rich matrix (5–10 wt.% H2O) with minor sediments (9:1 ratio) at fore-arc (∼65 km) to sub-arc (∼95 km) depths (2–3 GPa and 800–1250 °C) and compare to that of chlorite-rich mélanges from the literature. Our results show that the solidus of serpentine-rich matrices is between 1050 and 1100 °C and requires either diapiric rise of the mélange into the hotter mantle wedge or interactions with a hotter asthenosphere through slab tears to partially melt and produce basaltic melts, whether in hot or cold slab channels. Chlorite-rich mélanges may account for the sources of some arc lavas, but partial melting of serpentine-rich mélanges produce melts depleted in CaO, TiO2, alkalis, and are highly enriched in MgO compared to basaltic arc lavas. Both serpentine-rich and chlorite-rich matrices dehydrate to form denser peridotite and lose buoyancy at ∼800 °C and ≥1000 °C, respectively. Even if diapirism initiates in such mélanges near the slab-mantle interface, they would likely lose buoyancy upon ascent into the hotter mantle wedge resulting in stalled or failed diapirs. Diapir growth (τa) is controlled by the interplay of density, thickness and viscosity of the mélange, as well as the timescale of slab subduction (τs) and thermal structure of the subduction zone. We observe that the onset of diapirs in cold subduction zones requires mélanges that may sometimes be thicker than that observed by field and geophysical studies, while hot subduction zones overall require thinner mélanges. Thus, ultramafic-rich mélange diapirs may occur but only under specific conditions and when the diapiric ascent timescale is faster than the thermal equilibration barrier of ∼800–1000 °C (especially at the core of the mélange). Dehydration or partial melting of ultramafic-rich mélanges can affect the large ion lithophile element (LILE), volatiles, and high-field strength element (HFSE) budgets in the mantle wedge. Partial melting (caused by a diapiric rise or slab tear) does not fractionate LILEs from HFSEs at T ≥ 1100 °C and if the mélange has a lower LILE/HFSE to begin with, that signature is transferred to arc sources. Dehydration releases aqueous fluids rich in fluid-mobile elements (LILE and volatiles) relative to HFSE. Thus, the characteristic high LILE/HFSE signature of aqueous fluids is transferred to arc magma sources. Given high LILE/HFSE ratio is a ubiquitous arc magma signature, but slab tears are not, and diapirism in ultramafic-rich mélanges is highly conditional, this study corroborates that aqueous fluids released from sediment-starved mélanges are the predominant mass transfer agents rather than diapirs.

Macromycetes Determined in Aluçdağı Nature Park (Çamlıdere-Ankara) and its Close Environs

The study is based on the macrofungi samples collected from Aluçdağı Nature Park and its environs between the years 2021 and 2024. As a result of field and laboratory studies, 124 macrofungi species belonging to 2 divisions, 4 classes, 15 orders, 50 families and 86 genera were determined. The list of the species is presented together with their localities, habitat or substrates, collection dates and voucher numbers.

From unknown to familiar: An exploratory longitudinal field study on occupational exoskeletons adoption

Occupational exoskeletons hold promise in preventing musculoskeletal disorders, but their effectiveness relies on their long-term use by workers.This study aims to characterize the adoption process of occupational exoskeletons by analyzing the experiences of 25 operators. Using a mixed-methods approach, both quantitative and qualitative data were collected before and during a four-week familiarization period. We primarily focused on users' expectations, subjective assessments over time, and initial experiences.Findings elucidate shifts in operators' perceptions of the devices over time. Through their narratives, we highlight how exoskeleton use impact operators' movements and the subsequent adaptations. Operators demonstrated diverse exploratory behaviors, indicating their efforts to get to grips with the effects of exoskeletons in their own ways.This study offers insights into the initial stages of occupational exoskeleton adoption, thus enriching our comprehension of rejection patterns and pathways toward their widespread acceptance.

The microbiome of continuous wheat rotations: minor shifts in bacterial and archaeal communities but a source for functionally active plant-beneficial bacteria

Continuous wheat cropping often leads to yield decline, with suspected causes including increased pathogen susceptibility, decreased root growth, or low nutrient use efficiency, though the exact causes remain unknown. Here, we investigated soil and root-associated bacterial and archaeal communities in wheat under rotation versus continuous cultivation, monitored fungal pathogen presence, and used beneficial bacteria to mitigate Gaeumannomyces tritici (Ggt) symptoms in greenhouse experiments. Sampling was conducted at two field sites with different soil textures over two years and at two plant developmental stages, capturing site-specific and seasonal fluctuations. By cultivation, 767 bacterial isolates were screened for plant-beneficial traits. Amplicon sequencing revealed minor effects on community structure due to wheat rotational position but pronounced effects related to site, year, and microhabitat. Rhizoplane isolates with plant-beneficial traits were mainly Flavobacterium, Microbacterium, Pedobacter, Pseudomonas, Stenotrophomonas, and Variovorax. Continuous wheat rotations showed the highest proportion of bacteria with fungal antagonistic potential, indicating plant roots’ recruitment of beneficial bacteria. Introducing Ggt in the greenhouse experiment altered the bacterial and archaeal community, confirming field study results and demonstrating that applying beneficial bacteria early in the season at the seedling stage can control Ggt and improve plant growth. This study highlights the dynamic nature of wheat's below-ground bacterial and archaeal community, influenced by soil type, season, and microhabitat, with wheat rotation playing a minor role. In addition, it confirms the potential of selected Bacillus and Pseudomonas isolates, whether used individually or in consortia, for microbe-assisted mitigation of yield decline in intensive wheat production.

Evaluation of Coloured Sticky Traps for Monitoring the Population of Budfly, Dasyneura lini on Linseed Crop

A field study was conducted at Indira Gandhi Krishi Vishwavidyalaya Raipur, Chhattisgarh Rabi 2022-23 and 2023-24 to evaluate the use of different coloured sticky traps to assess the colour magnestism of budfly infecting linseed. The attractiveness of nine colour yellow, light yellow, blue, light blue, white, green, grey, pink, orange, brown, black and transparent (check) were evaluated during 2022-23 and 2023-24. Among the colour sticky traps average budfly attracted were maximum in the yellow coloured sticky traps during both the seasons with the cumulative value of 14.62 budfly/trap. The highest number of budfly trapped in yellow-coloured sticky trap over the crop growth period than other sticky traps. Lowest number of budfly catches were recorded in black traps in this experiment.

Diversity of Birch and Alder Forests in the Kostanay Region of Kazakhstan

This study delves into the phytocenotic structure and biodiversity of forest ecosystems dominated by species of the family Betulaceae (Betula pendula, Betula pubescens, and Alnus glutinosa) in the Kostanay region of Kazakhstan. The research is a significant step toward understanding the influence of environmental factors, particularly hydrological regimes and soil conditions, on the formation and functioning of these forest communities. Field studies were conducted across multiple plots, where detailed geobotanical descriptions and analyses of species diversity were performed. The results underscore the significant species diversity, with 146 vascular plant species identified across various forest types, and are of great importance. Birch forests exhibit higher species diversity than alder forests, with the highest diversity observed in plots with favourable moisture conditions. The study concludes that the hydrological regime is critical in shaping these forest ecosystems’ phytocenotic structure and productivity. These conclusions underline the importance of biodiversity conservation and sustainable forest management in the region, making the implications of this research significant and far reaching.

The Impact of Human Resources Management Practices on Green Innovation: A Field Study at Yemeni Pharmaceutical Industrial Companies in the Capital Municipality of Sana’a

The study aimed to measure the level of human resource management practices (HRMPs) and the level of green innovation achievement in Yemeni pharmaceutical companies in the Capital Municipality of Sana’a, as well as to measure the impact of human resource management practices on green innovation in the companies under study. The descriptive-analytical approach was employed, and a questionnaire was developed as the tool of data collection. The population was (1675) employees from all administrative levels in seven Yemeni pharmaceutical industrial companies in Sana’a. The questionnaire was distributed to the study sample (313) of which (240) were valid for statistical analysis. The findings revealed that the level of achievement of HRMPs in the companies under study was high, and the level of green innovation achievement was also high. The study also found that there is a significant impact of HRMP on green innovation in the companies under study, with the motivation and compensation dimension having the greatest impact on green innovation, followed by the performance appraisal dimension, and then the job design dimension. However, the study found no statistically significant impact of training and development of human resources and recruitment dimensions on green innovation. The study recommends that companies should pay more attention to the current policies followed in job design, selection and recruitment of employees, and training and development programs designed for them. In addition, companies should improve and develop compensation and incentive systems and link them to performance appraisal systems and pay more attention to environmental practices for human resource management.

Shamans and “Dark Agencies”: War, Magical Parasitism, and Re-Enchanted Spirits in Siberia

Alleged practices of magical assault and vampirism are a recurrent feature of popular explanations of misfortune in Tuva, South Siberia. Based on a field study of healing practices in an “Association of Shamans”, this article analyses rituals of redressing curse afflictions in the context of Russian political domination. A central purpose of this discussion is to foreground the centrality of kinds of parasitical worship and occult threat to structures of political power in—and beyond—the territory of Tuva. Focusing on a “cursescape”, which develops from the combative practices of shamans, occult specialists, and office-holders, the article probes a repertoire of shamanic healing symbols. It is argued that healing efficacy is constructed in the process of engaging with hunting symbols and animal spirits, which appear in Indigenous Siberian cosmologies. The analysis shows that ideas of ritual risk underpin the process of symbolic resolution. Whereas shamanic practices provide refuge to spirits evicted from their natural landscapes, Tibetan Buddhism—the unifying religion of Tuva—offers an alternative path of healing the effects of the shamans’ propagation of spirits. The article highlights indigenous perceptions of a “cursed” landscape as a space where the agencies of “darkness” and their political sponsors are confronted with an emancipating religious modality emerging from local Buddhist rituals. The analysis displays the unsolved drama of itinerant spirits and shamanic ancestral souls, whose agency is revealed through successive—yet inauspicious—forms of reincarnation.

Phase Field Study of Discontinuous Precipitation in a Miscibility Gap System

AbstractA phase field model is developed to study the discontinuous (cellular) precipitation (DP) reaction in a hypothetical A-B miscibility gap system. Unlike previous treatments, the model employs an interaction energy term which couples the composition and the phase field variable to enable the necessary grain boundary movement. The influence of factors such as interaction energy, interfacial mobility and grain boundary diffusivity on the transformation rate and overall microstructure evolution are discussed.

I am just a sister: a field study on sister as mother role from Guangdong, China.

This study aimed to explore sister-as-mother (jieximuzhi) roles in families after the implementation of China's universal two-child (quanmianerhai) and three-child policies (saihaizhengce). By conducting in-depth interviews with 10 sisters from Guangdong Province who fit the sister-motherhood profile, this study investigated their motivations for taking on maternal duties, the characteristics of sister-motherhood roles, and the impact of these roles on the sisters. The results revealed that in families with two or more children, sisters passively assume mother-like responsibilities primarily due to biological age differences and parental neglect, as well as their personal initiative to a certain extent. Additionally, the impact of sister-motherhood roles on sisters includes aspects such as time pressure, financial strain, and increased family intimacy. This study elucidated the phenomenon of sister-motherhood roles that emerge with changes in family structure in China while recognizing the diversity of women's roles within the family, appreciating the challenges faced by sisters in sister-motherhood roles, and providing insights into family labor division and education models.

Fiber flax varieties of domestic selection under conditions of the Tomsk region

The results of the study of 20 samples of cultivated flax (Linum usitatissimum L.) of the Federal Scientific Center of Bast Crops in 2021–2023 are presented. The field studies were conducted in the sub-taiga zone of the Tomsk region. Natural and climatic conditions corresponded to the requirements of fiber flax cultivation. As a result of the conducted research, valuable and flexible source material for the creation of varieties with high productivity traits has been identified. The varieties of the Pskov selection – Antey, Voskhod, Nord, Chance, Tver (Torzhok) selection – Polet, Universal, Smolensk selection – Phoenix, Impulse and standard Pamyati Krepkova – stood out in terms of total and technical length of the stems. The total stem length reached 90 cm and above, the technical stem length was more than 80 cm. The leaders in terms of fiber content in the technical part of the stems were varieties of the Tver selection (Torzhok): Tonus, Visit, Pskov varieties – Kvartet, Orion, Peresvet – 40% and higher. The highest value for the characteristic of stem slenderness (the ratio between technical length and stem thickness) was observed in the varieties Voskhod (681.0) and Peresvet (652.6). In terms of linear stem density, the varieties differed insignificantly among themselves, with most varieties having values in the range of 5.0–6.0 mg/cm. The influence of the factor " The year of inclusion in the State Register of BA of the Russian Federation" was also studied. The factor had the greatest influence on the fiber content trait. Varieties with earlier dates of inclusion in the State Register showed low fiber yield. Russian flax varieties are recognized as promising and are included in the breeding process as male and female seed parents during hybridization.

A Novel Method for Early Warning and Quantitative Evaluation of Liquid Loading in Gas Wellbore Based on Dynamic Production Data: A Case Study of Linxing Tight Gas Field

A Novel Method for Early Warning and Quantitative Evaluation of Liquid Loading in Gas Wellbore Based on Dynamic Production Data: A Case Study of Linxing Tight Gas Field