Field Sites Research Articles

Prevalence of diarrhoea and treatment-seeking practices among children

Estimating the proportion of children with diarrhoea and those who are taken in as inpatients or outpatients is important for policy planning, resource allocation, and to evaluate the effectiveness of diarrhoea prevention and control interventions. We aimed to estimate the proportion of children <2 years of age with diarrhoea, explore their treatment-seeking practices, and identify factors associated with both diarrhoea and treatment seeking. We designed a longitudinal study based on a sample of children <2 years of age in the Birhan field site from September 2018 to September 2019. The study site collected data on child mortality and morbidity and treatment-seeking practice for those with a history of illness every three months. Mothers/caregivers were asked about signs or symptoms of illnesses for a two-week period prior to each study visit. We estimated the proportion of children <2 years of age with diarrhoea and treatment-seeking practices for each of the four rounds of data collection and identified associated factors through bivariable and multivariable logistic regression. We enrolled 4678 children <2 years of age. The proportion of children with diarrhoea was the highest from 11 September 2018 to 9 December 2018 (4.47%; 95% confidence interval (CI) = 3.70-5.35) and the lowest from 10 December 2018 to 9 March 2019 (2.48%; 95% CI = 1.90-3.19). Children from households with chlorinated drinking water had a 50% (adjusted odds ratio (aOR) = 0.50; 95% CI = 0.28-0.88) lower odds of developing diarrhoea compared to those who did not. Among 339 children with diarrhoea, 275 (81.12%; 95% CI = 76.54-85.15) were taken to health facilities for treatment. Female children had lower odds of being taken to health facilities for treatment (aOR = 0.37; 95% CI = 0.17-0.80) compared to males. While the proportion of children with diarrhoea in our study was lower than that observed in prior research conducted in Ethiopia, treatment-seeking practices were higher. Female children and children from the poorest families had lower odds of treatment. We recommend more studies to explore gender-based and socioeconomic differences affecting treatment-seeking practices.

“Like Us, but Not Quite Us”: Researching Gender Politics in Autocratic Contexts

What challenges do researchers encounter in authentically engaging with the field site and academia when certain aspects of their true identities diverge from the established norms within those domains? Using the case of female political scientists who conduct research on gender politics in the Middle East and North Africa, I highlight the ethical, logistical, and epistemological challenges of carrying out research in a politically and socially closed context. Few studies have investigated how the research process and the knowledge it produces are affected by the intertwinement of authoritarianism and patriarchy, and by the researcher’s positionality within this context. This study fills this gap by drawing upon interviews with feminist political scientists who were born and raised in the region but are based in Western academic institutions to examine the impact of authoritarianism, patriarchy, and the researchers’ insider/outsider positionality on the research process. The analysis shows three key findings. First, researching gender politics is a contentious topic that places researchers on the radar of the state. For scholars who are originally from the region, the issue is compounded by the fact that they are sometimes viewed as traitors by the regime in their country of origin, which accuses them of tarnishing the image of the government and scrutinizing its gender policies. Second, within the wider society, the politics of representation also impose certain limitations and expectations on female scholars. Such limitations include gendered restrictions on their access and mobility in the field. Finally, feminist researchers share how the knowledge they produce, which centers social justice demands, is not always valued in the discipline of political science. The article contributes to this discipline by expanding our understanding of the interplay between identity politics, fieldwork practices, and knowledge production in complex political and social settings.

Intraspecific trait variability in wild plant populations predicts neither variability nor performance in a common garden

Dryland restoration requires plant materials capable of performing well despite difficult growing conditions. Selecting plant materials with higher intraspecific trait variability (ITV) may support successful outcomes by enhancing the performance of those materials in restoration settings. However, maintaining ITV from wild populations is not well understood and requires further investigation if ITV is to be incorporated into native plant materials, which are often developed from wild‐collected seed grown in agricultural settings. We used two perennial plant species to explore whether (1) ITV measured at field sites predicts ITV in a common garden, (2) rankings of ITV among populations remain stable over time, and (3) higher levels of ITV promote survival and reproductive effort in a common garden. We measured ITV in specific leaf area and height for Bouteloua curtipendula and Heterotheca villosa at field sites and over 2 years in a common garden, as well as survival and flower production in the common garden. We also calculated climate distance between field sites, where seeds were originally sourced, and the common garden to account for the impact of climatic differences on ITV. We found that (1) ITV measured at field sites did not predict ITV in the common garden, (2) rankings of ITV across populations were inconsistent, and (3) relationships between ITV and performance were rare and differed by species. Our findings indicate that the utility of ITV in wild populations as a predictive tool may be limited.

Unravelling Coupled Hydrological and Geochemical Controls on Long-Term Nitrogen Enrichment in a Large River Basin.

Many groundwater and surface water bodies around the world show a puzzling and often steady increase in nitrogen (N) concentrations, despite a significant decline of agricultural N inputs. This study uses a combination of long-term hydrogeochemical and hydraulic monitoring, molecular characterization of dissolved organic matter (DOM), column experiment, and reactive transport modeling to unravel the processes controlling N-reactive transport and mass budgets under the impacts of dynamic hydrologic conditions at a field site in the central Yangtze River Basin. Our analysis shows that the desorption of ammonium (NH4+) from sediments via cation exchange reactions dominates N mobilization and aqueous N concentrations, while the mineralization of organic N compounds plays only a minor role. The reactive transport modeling results illustrate the important role of cation exchange reactions that are induced by temporary NH4+ input and cation concentration changes under the impact of both seasonal and long-term hydrologic variations. Historically, cation exchangers have acted as efficient storage devices and mitigated the impacts of high levels of NH4+ input. The NH4+ residing on cation exchanger sites later acts as a long-term N source to waters with the delayed desorption of sediment-bound NH4+ induced by the change of hydrologic conditions. Our results highlight the complex linkages between highly variable hydrologic conditions and NH4+ partitioning in near-surface, river-derived sediments.

Synergistic effect of pyridate-based herbicide mixtures for controlling multiple herbicide-resistant kochia

Abstract Multiple herbicide classes resistant (MHCR) kochia poses a serious concern for producers in the Central Great Plains, including western Kansas. Greenhouse and field experiments were conducted at Kansas State University Research and Extension Centers near Hays and Garden City, KS to evaluate pyridate-based postemergence (POST) herbicide mixtures for controlling MHCR kochia. One previously confirmed MHCR population (resistant to atrazine, glyphosate, dicamba, and fluroxypyr) and a susceptible (SUS) kochia population were tested in a greenhouse study. The kochia population at Hays field site was resistant to atrazine, dicamba, and glyphosate while kochia population at Garden City site was resistant to atrazine and glyphosate. Colby’s analysis revealed synergistic interactions when pyridate was mixed with atrazine, dicamba, dichlorprop-p, fluroxypyr, glyphosate, or halauxifen/fluroxypyr and resulted in ≥94% control and shoot dry biomass reduction of MHCR kochia in a greenhouse study. Similarly, synergistic interactions were observed for MHCR kochia control in fallow field studies at both sites when pyridate was mixed with glyphosate or atrazine. Kochia control was increased from 26% to 90% with the application of glyphosate + pyridate and from 28% to 95% with atrazine + pyridate at both sites as compared to separate applications of glyphosate or atrazine. This is the first report for such a strong synergistic effect for both glyphosate and atrazine mixtures with pyridate on a weed resistant to both. All other pyridate-based herbicide mixtures showed an additive interaction and resulted in better control of MHCR kochia (87 to 100%) as compared to their individual applications (23 to 92%) across both sites except 2,4-D. These results suggest that pyridate can play a crucial role in various POST herbicide mixtures for effective control of MHCR kochia.

Agroecological importance of smooth brome in managing wheat stem sawfly (Hymenoptera: Cephidae) via associated braconid parasitoids.

Wheat stem sawfly (WSS), Cephus cinctus Norton (Hymenoptera: Cephidae), is a major pest of cereal crops throughout the Northern Great Plains of North America. Native parasitoids, Bracon cephi (Gahan) and B. lissogaster Muesebeck (Hymenoptera: Braconidae), play a key role in suppressing WSS populations and limiting associated damage. Smooth brome grass (Bromus inermis Leyss.) serves as a potential trap reservoir for WSS when grown in areas surrounding wheat (Triticum aestivum L.) fields in Montana. Its unique biology allows it to support high WSS infestation while promoting significant larval mortality throughout the growing season. Late-season WSS survivors can then serve as hosts for WSS parasitoids. Our study investigated smooth brome as a host refuge for WSS parasitoids. We measured WSS larval infestation and survival rate inside smooth brome grown within WSS-inclusion cages, finding a maximum infestation of 66.5% and an end-of-year WSS survival of 5.7%. In addition, we collected stems from sites in central and north-central Montana to measure the WSS infestation and parasitoid prevalence in wheat and adjacent smooth brome. WSS infestation was high in both Big Sandy (64.5% smooth brome, 65.7% adjacent wheat) and Moccasin, MT (50.6%, 38.6%). Year-end WSS larval mortality was 43.6% greater in smooth brome compared to adjacent wheat at both field sites, but both hosted similar numbers of WSS parasitoids. This research underscores the importance of smooth brome in providing a sustainable host refuge for WSS parasitoids and highlights its significant role in supporting the economics of wheat cultivation.

Microbial Community Analysis Offers Insight into the Complex Origins of Plant Disease in a Smallholder Farm Context

Classical approaches to plant disease diagnosis assume a single pathogen/single disease paradigm. Here, we revisit the presumed role of Fusarium oxysporum as the causal agent of wilting and yellowing of chickpea plants on smallholder farms in Ethiopia. Contrary to expectations, detection of Fusarium DNA using conserved PCR primers failed to associate the pathogen with symptomatic plants. Instead, culture-independent sequencing of microbial communities nominated unexpected pathogens and revealed patchiness in the assembly of common microbial consortia. Surprisingly, tests of differential enrichment identified Phytophthora as the most common disease-associated taxon. More generally, across all field sites, multilevel pattern analysis identified indicator taxa whose patterns of co-occurrence demarcate discrete microbial communities and are consistent with a range of specific interactions, including mutualism and antagonism. Taken together, these data indicate that soilborne chickpea disease in Ethiopia has heterogeneous origins and that despite decades of emphasis and disease resistance breeding, the role of Fusarium as the frequent agent of chickpea disease in Ethiopia remains enigmatic.

Confirmation of synthetic auxin herbicide resistance in a green pigweed (Amaranthus powellii) population from Ontario, Canada

Abstract Following the application of MCPA/MCPB at 1.7 kg ae ha−1 at a field site near Dresden, ON, Canada, poor control (&lt;50% visible control) of green pigweed (Amaranthus powellii S. Watson) was observed. Amaranthus powellii is a common weed in Ontario crop production, and its evolution of resistance to synthetic auxin herbicides (SAHs) could pose a risk to crop yields. The suspected resistant A. powellii population (R) was used in dose–response and field experiments to determine resistance to SAHs. The objective of these studies was to determine whether this population of A. powellii is resistant to MCPA and cross-resistant to other SAHs. The GR50 (herbicide dose that causes a 50% reduction in plant aboveground biomass) values were determined by fitting plant dry weight data, obtained following application with seven SAHs, to a four-parameter log-logistic equation and were compared between the suspected-resistant (R) population and a known susceptible (S) population of A. powellii. The field trial was conducted in 2017, 2018, 2019, and 2021 in corn (Zea mays L.) and consisted of 11 postemergence SAH treatments. The GR50 values differed between the R and S populations following application with MCPA, aminocyclopyrachlor, dichlorprop-p, and mecoprop, resulting in resistance factors of 4.4, 3.0, 2.5, and 2.4, respectively. In the field study, dicamba and MCPA ester controlled A. powellii 84% and 30%, respectively, at 8 wk after treatment application (WAA). The control of Amaranthus powellii with all SAHs applied POST in corn was poor (&lt;90% visible control) at 8 WAA. Both studies confirmed resistance to SAHs in this population of A. powellii, which will create limitations for farmers aiming to control this weed.

Non-target screening reveals 124 PFAS at an AFFF-impacted field site in Germany specified by novel systematic terminology.

The uncontrolled release of aqueous film-forming foam (AFFF) ingredients during a major fire incident in Reilingen, Germany, in 2008 led to significant soil and groundwater contamination. As the identity of fluorochemical surfactants in AFFF are often veiled due to company secrets, it is important to characterize AFFF contaminations and their impact on the environment comprehensively. In this study, we adapted a systematic approach combining a suitable extraction method with liquid chromatography high-resolution quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) for an extensive non-targeted analysis. Our analysis identified 124 per- and polyfluoroalkyl substances (PFAS) from 42 subclasses in the contaminated soil (confidence levels of identification between 1 and 3). Typical for AFFF-impacted field sites, these included anionic, cationic, and zwitterionic substances with perfluoroalkyl chains spanning from 3 to 14 carbon atoms. Furthermore, we identified 1 previously unreported substance, and detected 9 PFAS subclasses for the first time in soil. AFFFs have long been employed to extinguish large hydrocarbon fires, yet their environmental consequences remain a concern. This study sheds light on the complex composition of AFFFs at this particularly contaminated area, emphasizing the necessity for extensive contaminant characterization as sound basis for informed management strategies to mitigate their adverse effects. AFFF PFAS are often named differently in the literature, leading to inconsistency in terminology. To address this issue, we introduced partially new terminology for AFFF-related PFAS to establish consistent terminology, to facilitate communication of identified compounds, and to ensure that the chemical structure can be directly derived from acronyms.

Variability in spruce beetle (Coleoptera: Curculionidae, Scolytinae) adult diapause and evidence for oocyte development prior to winter in a Colorado population.

Diapause regulates seasonal insect life cycles and may be highly variable within and among populations due to genetic and environmental variability. Both types of variation may influence how populations respond plastically or evolutionarily to changing climates. We assessed diapause variability in spruce beetle Dendroctonus rufipennis Kirby (Coleoptera: Curculionidae, Scolytinae), a major forest pest whose life cycle timing is regulated by both prepupal and adult diapauses. Using mating studies and ovary dissections, we tested for variability in adult diapause within and between collection sites in Colorado and Wyoming, USA. Ovary morphology suggested that most females from both sites enter diapause prior to egg formation (oogenesis) when reared at warm temperatures. Though previous studies suggested that adult diapause is obligate, we found that a small proportion of females from both populations terminated diapause without winter chilling in the lab. Moreover, we found that most female beetles sampled at the Colorado field site had mature ovaries relatively early in the fall, suggesting that transient exposure to low temperatures may potentiate pre-winter reproductive development. Adult diapause may act primarily as a block to prevent offspring production late in the season but not necessarily as an overwintering phenotype. Overall, our data do not suggest imminent life cycle shifts mediated by adult diapause, but if the observed variability is heritable, diapause regulation may evolve in response to changing environmental conditions.

Spatial and temporal characterization of Aedes albopictus oviposition activity in candidate urban settings for sterile insect technique testing in La Reunion Island

BackgroundUnderstanding of mosquito spatiotemporal dynamics is central to characterize candidate field sites for the sterile insect technique (SIT) testing, and is critical to the effective implementation and evaluation of pilot sterile male release programs. Here, we present a detailed description of Aedes albopictus (Skuse) egg-laying activity over a 6-year period in urban areas identified as potential SIT testing sites on Reunion Island.MethodWeekly entomological collections using ovitraps were carried out in residential and adjacent uninhabited habitats in two urban areas, Duparc and Bois Rouge, in the municipality of Sainte Marie, Reunion Island. Time-series data incorporating the frequency of positive ovitraps and the total number of eggs/ovitrap recorded each time at each locality during the study period from May 2013 to December 2018 were analyzed with multifaceted statistical approaches including descriptive statistics and spatiotemporal analyses incorporating the role of climatic factors on overall ovitrap productivity.ResultsDuring the ovitrap survey, the proportion of egg-positive ovitraps differed among study sites (χ2 = 50.21, df = 2, P < 0.001), being relatively lower in Duparc (89.5%) than in Bois-Rouges (95.3%) and the adjacent buffer zone (91.2%). Within each neighborhood, Ae. albopictus egg abundance varied by month in a roughly seasonal pattern marked by a single peak occurring more regularly February each year, a decline at the onset of the austral winter in July, followed by a period of lower ovitrap productivity in August and September. Fluctuation in both positivity rate and eggs densities per ovitraps were related to annual and seasonal variations in local temperature and rainfall (P < 0.001 in all cases). The spatial analysis also captured substantial between- and within-habitats heterogeneity, whereby the overall ovitrap productivity was higher in residential areas than in the buffer zone.ConclusionsCollectively, these results reveal that the distribution of Ae. albopictus oviposition activity is shaped by local habitat heterogeneity and seasonal climatic factors. Overall, this study provides baseline insights into the reproductive dynamics of Ae. albopictus, which would assist in planning locally tailored SIT interventions, while addressing concerns related to focal areas of high egg-laying intensity and potential immigration of females from natural areas.

Tectonic Inversion in Sediment-Hosted Copper Deposits: The Luangu Area, West Congo Basin, Republic of the Congo

Complex Neoproterozoic tectonic processes greatly affected the West Congo Basin, resulting in a series of dispersed copper deposits in the Niari Sub-basin, Republic of the Congo. Structural observation and analysis can help in understanding both the transportation pathways for copper accumulation and the detailed tectonic evolution processes. This study examines cases from four copper mine sites in the Luangu region of the Niari Basin, using a set of codes that consider the three regional tectonic regimes (extension, extrusion, and contraction) and three deformation criteria (maximum effective moment criterion, tensile fracture criterion, and the Coulomb criterion). By combining these two aspects, nine new codes are introduced: the extension maximum effective moment criterion (EM), extension tensile fracture criterion (ET), extension Coulomb criterion (EC), strike-slip maximum effective moment criterion (SM), strike-slip tensile fracture criterion (ST), strike-slip Coulomb criterion (SC), compression maximum effective moment criterion (CM), compression tensile fracture criterion (CT), and compression Coulomb criterion (CC). By analyzing and applying these codes to the selected sites, we show that the new codes can present a geometric coordination catering to an exhumation-related inversion process from extension, strike-slipping, to contraction. The existence of SM- and CM-related structures that occurred during regional extrusional and contractional events may indicate a deeper level of exhumation for layers related to copper deposits in the field sites. A new tectonic evolution model is presented, considering the hypothesis of vertical principal stress changes while the two horizontal principal stresses remain relatively constant during copper mineralization affected by the Western Congo Orogen. The application of the nine codes facilitates the determination of interrelations between different tectonic regimes.

Intraspecific variability in plant and soil chemical properties in a common garden plantation of the energy crop Populus.

Optimizing crops for synergistic soil carbon (C) sequestration can enhance CO2 removal in food and bioenergy production systems. Yet, in bioenergy systems, we lack an understanding of how intraspecies variation in plant traits correlates with variation in soil biogeochemistry. This knowledge gap is exacerbated by both the heterogeneity and difficulty of measuring belowground traits. Here, we provide initial observations of C and nutrients in soil and root and stem tissues from a common garden field site of diverse, natural variant, Populus trichocarpa genotypes-established for aboveground biomass-to-biofuels research. Our goal was to explore the value of such field sites for evaluating genotype-specific effects on soil C, which ultimately informs the potential for optimizing bioenergy systems for both aboveground productivity and belowground C storage. To do this, we investigated variation in chemical traits at the scale of individual trees and genotypes and we explored correlations among stem, root, and soil samples. We observed substantial variation in soil chemical properties at the scale of individual trees and specific genotypes. While correlations among elements were observed both within and among sample types (soil, stem, root), above-belowground correlations were generally poor. We did not observe genotype-specific patterns in soil C in the top 10 cm, but we did observe genotype associations with soil acid-base chemistry (soil pH and base cations) and bulk density. Finally, a specific phenotype of interest (high vs low lignin) was unrelated to soil biogeochemistry. Our pilot study supports the usefulness of decade-old, genetically-variable, Populus bioenergy field test plots for understanding plant genotype effects on soil properties. Finally, this study contributes to the advancement of sampling methods and baseline data for Populus systems in the Pacific Northwest, USA. Further species- and region-specific efforts will enhance C predictability across scales in bioenergy systems and, ultimately, accelerate the identification of genotypes that optimize yield and carbon storage.

A new combined transient electromagnetic noise reduction method of VMD-SVD-WTD based on improved dung beetle optimization algorithm with multi-strategy fusion

Abstract The transient electromagnetic method (TEM) is now commonly used in the detection of coal mined-out areas, but it is susceptible to various sources of noise during field site probing, significantly impacting the accuracy of detection. Variational mode decomposition (VMD) has gained widespread adoption for eliminating noise in TEM signals. However, a single VMD may not effectively address both full-band noise and residual Gaussian white noise. To address this limitation, the singular value decomposition (SVD) and wavelet threshold denoising (WTD) are introduced correspondingly. Furthermore, this paper tackles challenges related to parameters selection in VMD and traditional optimization algorithms by proposing the integration of dung beetle optimization (DBO) enhanced with circle chaotic mapping, random walk strategy, and crisscross optimization algorithm (CRCDBO). Consequently, a new combined TEM noise reduction method, VMD-SVD-WTD based on CRCDBO is presented. Through comprehensive simulation tests and comparative analyses, the signal-to-noise ratio of this method is improved by 12.79% compared with VMD and the RMSE is 0.0011, which demonstrate the superiority and effectiveness of VMD-SVD-WTD based on CRCDBO in noise reduction. Meanwhile, this method is applied to an iron ore mine in Shanxi, which can accurately monitor the location of the mined-out area and has good application value.

Advanced optimization of elastic sheets for solar parabolic trough concentrators: integrating particle swarm optimization and genetic algorithms

Abstract The fabrication of solar parabolic trough concentrators using flat elastic sheets presents a straightforward and cost-effective method. This paper introduces an optimization technique centered on stiffness adjustment, harnessing elastic buckling to attain precise parabolic shapes in these concentrators. Through an enhanced Particle Swarm Optimization-Genetic Algorithm (PSO-GA), strategically punched holes are optimized on the flat sheet, allowing for the attainment of perfect parabolic shapes by controlling the chord length with a positional rod or cable. The efficacy of this approach is showcased not only through interactive finite element analysis and ray tracing software simulations but also via experimental sunlight concentration. A geometric concentration ratio of up to 145.16 is achieved, underscoring the effectiveness of this innovative concept. This approach facilitates the simple fabrication and transportation of flat mirror elements to field sites, where they can be assembled into parabolic trough concentrators, offering potential cost reductions and highly efficient solar energy solutions.

Rising temperatures may increase fungal epizootics in northern populations of the invasive spongy moth in North America

Insect pest species are generally expected to become more destructive with climate change because of factors such as weakened host tree defences during droughts and increased voltinism under rising temperatures; however, responses will vary by species due to a variety of factors, including altered interactions with their natural enemies. Entomopathogens are a substantial source of mortality in insects, but the likelihood of epizootics can depend strongly on climatic conditions. Previous research indicates that rates of infection of the spongy moth (Lymantria dispar) by its host-specific fungal pathogen, Entomophaga maimaiga, increase with environmental moisture and decrease as temperatures rise. High temperatures may have direct and indirect (due to the associated drying) effects on the fungus, but the interactive effects between temperature and moisture level on larval infection are unclear. Here, we test the hypothesis that warmer, drier conditions will decrease rates of infection of spongy moth larvae by E. maimaiga. We evaluated the effects of precipitation and temperature on larval mortality caused by E. maimaiga with a manipulative field experiment, conducted in one of the northernmost and coldest parts of the spongy moth’s non-native range in North America. We caged laboratory-reared spongy moth larvae in experimentally warmed open-air forest plots, exposing the larvae to soil inoculated with E. maimaiga resting spores during two consecutive trials. Caged larvae were exposed to three temperature treatments — ambient, 1.7 °C above ambient and 3.4 °C above ambient — and either supplemental precipitation (+173 mm per trial) or ambient precipitation. Opposite to our hypothesis, there was no significant effect of supplemental precipitation, nor an interaction between precipitation and temperature. There was, however, a significant positive effect of increasing temperature on the number of larvae infected. On average, in each respective trial, larval infection increased by 44% and 50% under the elevated temperature treatments compared to ambient temperature. Experimental warming may have increased infections because ambient temperatures at the field site were suboptimal for fungal germination. The results from this experiment suggest that, in colder portions of the spongy moth’s invasive range, increasing temperatures due to climate change may enhance the ability of E. maimaiga to help control populations of the spongy moth.

ESPressoscope: A small and powerful approach for in situ microscopy.

Microscopy is essential for detecting, identifying, analyzing, and measuring small objects. Access to modern microscopy equipment is crucial for scientific research, especially in the biomedical and analytical sciences. However, the high cost of equipment, limited availability of parts, and challenges associated with transporting equipment often limit the accessibility and operational capabilities of these tools, particularly in field sites and other remote or resource-limited settings. Thus, there is a need for affordable and accessible alternatives to traditional microscopy systems. We address this challenge by investigating the feasibility of using a simple microcontroller board not only as a portable and field-ready digital microscope, but furthermore as a versatile platform which can easily be adapted to a variety of imaging applications. By adding a few external components, we demonstrate that a low-cost ESP32 camera board can be used to build an autonomous in situ platform for digital time-lapse imaging of cells. Our prototype of this approach, which we call ESPressoscope, can be adapted to applications ranging from monitoring incubator cell cultures in the lab to observing ecological phenomena in the sea, and it can be adapted for other techniques such as microfluidics or spectrophotometry. Our prototype of the ESPressoscope concept achieves a low power consumption and small size, which makes it ideal for field research in environments and applications where microscopy was previously infeasible. Its Wi-Fi connectivity enables integration with external image processing and storage systems, including on cloud platforms when internet access is available. Finally, we present several web browser-based tools to help users operate and manage our prototype's software. Our findings demonstrate the potential for low-cost, portable microscopy solutions to enable new and more accessible experiments for biological and analytical applications.

Artificial intelligence for predicting arctic permafrost and active layer temperatures along the Alaskan North Slope

AbstractClimate change in Arctic regions poses a threat to permafrost stability, potentially leading to issues such as infrastructure damage, altered ecosystems, and increased greenhouse gas emissions. The challenge of monitoring permafrost temperatures and identifying critical environmental factors is accentuated by the scarcity of subsurface thermal data in remote Arctic locales. To alleviate this lack of soil thermal data we set out to combine in situ observed soil temperatures with MERRA-2 reanalysis data and Machine Learning (ML) to develop local and season-specific subsurface soil temperature predictions in Alaska. First, reanalysis features are selected based on surface energy budget physics. Coupled with Julian calendar dates, reanalysis features are preprocessed and then fed to the ML prediction model. We conducted a series of computational experiments and tested the results against performance benchmarks to determine the optimal prediction models, length of look-back period of model inputs, and the training set size. Six conventional ML models (e.g., GBDT, RF, SVR) and five statistical baselines (e.g. ARIMA) using in situ time series of soil temperature data ranging from 0 - 1 m depth are considered for the prediction task. The models are trained using in situ soil temperatures at depths between 0 and 1 m, spanning 16+ years, from field sites at Deadhorse and Toolik Lake, Alaska. All prediction performances are assessed using root mean squared error (RMSE) and mean absolute error (MAE). Results show that locally trained ML models can estimate shallow soil temperatures with an average error of $$RMSE=1.308^{\circ }$$ R M S E = 1 . 308 ∘ C.

Применение новых технологий кислотной обработки пластов для восстановления продуктивности пласта

Oil recovery, measured by the oil recovery factor (ORF), is a key indicator of the efficiency of oil production. In Russia, the ORF decreased to 0.3 while in the United States this indicator increased to 0.4. About 90% of Russian oil is produced by large holdings, the structure of reserves is shifting towards hard-to-recover, which requires the use of new methods to increase oil recovery. Primary and secondary production allows only 20-50% of oil to be extracted, what makes the use of tertiary methods necessary. The development of horizontal wells with multistage hydraulic fracturing contributes to the development of new field sites, but requires careful preparation of wells to minimize risks and cost increases. Cleaning the bottomhole area using acidic formulations is often the only cost-effective way to restore the productivity of a horizontal well. The improved method of acid composition reduction using a guar gel with delayed “crosslinking”, which ensures uniform treatment of all productive zones of the formation is considered in article. The technology allows for continuous multi-stage acid treatment, temporarily blocking highly permeable areas and increasing the coverage of acidic effects on poorly drained areas. The calculation of the diverter volume considers the average efficiency of the liquid after mini-fracturing, adjusting the volume depending on the efficiency of the liquid at each port.

First Report of Dalbulus maidis (DeLong and Wolcott) (Hemiptera: Cicadellidae) in Oklahoma.

The corn leafhopper, Dalbulus maidis (DeLong and Wolcott) (Hemiptera: Cicadellidae), is an invasive insect that can cause damage to maize (Zea mays L.) in two ways: by direct feeding and the transmission of several plant pathogens. Dalbulus maidis is an invasive and serious economic pest of maize that has spread from its center of origin in Mexico to the southernmost parts of the United States. Prior to 2024, corn leafhoppers had not been documented in Oklahoma, and their spread northward toward the United States corn belt is of significant concern. Here, we provide the first reports of the insect in maize in several Oklahoma counties. Insect specimens were collected at various commercial and experimental field sites by Oklahoma State University research and extension personnel. The identity of the insect species was validated through morphological and molecular taxonomy. The presence records for the corn leafhopper presented here provide valuable information for future monitoring and management efforts of this economically important pest and disease.