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A common passive sampler used to measure NH3 volatilization losses in field studies has a nozzle with a 1‐mm, round orifice that reduces air flow to increase NH3 adsorption. This reduction in air flow, measured by the orifice's K value (0–1), implies a reduction in the amount of NH3 entering the sampler per unit of time, which may require a longer exposure to accumulate measurable quantities of NH3. Increasing the diameter of the orifice would increase the NH3 entering the sampler and possibly allow shorter exposure times, but it may also lead to increased NH3 bypass. The objectives of this research were to (1) determine the effect of wind speed on NH3 bypass in samplers with 1‐ or 2‐mm orifices, (2) determine the reduction in air speed in samplers with 1‐ or 2‐mm orifices by determining their K values, and (3) compare field NH3 volatilization losses measured with 1‐ and 2‐mm orifices. A laboratory study with wind speeds ranging from 0.6 to 10 m·s−1 showed that both orifice sizes had NH3 bypass at low and high wind speeds. Results from wind tunnel studies determined that flow was reduced to 63% (K = 0.63) in 1‐mm orifices and to 74% (K = 0.74) in 2‐mm orifices. Field studies indicated that 1‐mm orifices may measure greater NH3 volatilization losses than 2‐mm orifices at average low wind speeds when maximum wind speeds <10 m·s−1, but may measure equal or lower losses than 2‐mm orifices when several days occur with maximum wind speeds >10 m·s−1. Core Ideas: Field NH3 loss measured with 1‐ and 2‐mm orifices depended on maximum wind speeds.Ammonia bypass occurred at low and high wind speeds with both orifice sizes.Wind speed through sampler was reduced to 63% with a 1‐mm orifice and to 74% with a 2‐mm orifice. [ABSTRACT FROM AUTHOR]

Ureolytic microbes are abundant in broiler litter (BL), and previous research indicates that microbially induced calcium carbonate precipitation via urea hydrolysis occurs in gypsum‐amended litters. Given that calcium carbonate (CaCO3) is used to correct soil acidity, we hypothesized that the soil‐liming potential of BL + gypsum is greater than that of unamended litter. First, an experiment was conducted to isolate ureolytic bacteria from BL and confirm their ability to precipitate CaCO3. To determine the effects of calcium on urea hydrolysis, six isolates were identified from screenings of 30 colonies collected from different BL sources. Calcium increased the ureolytic rate by 29%–160% and the precipitation of CaCO3 by ~1500% in solution. The 16S rRNA of the isolate with the greatest rate of urea hydrolysis was sequenced and belong to Lysinibacillus macroides. Broiler litter amended with gypsum was inoculated with L. macroides and found to precipitate significantly more CaCO3 than inoculated litter without gypsum. Finally, over the course of a 28‐day incubation, the pH and inorganic‐N of soil, soil + BL, and soil + BL + gypsum were measured. Surprisingly, soil + BL + gypsum was found to have a significantly lower pH than soil + BL for the first 21 days. We propose that the decreased liming ability of BL + gypsum is due to a combination of pH buffering mechanisms and increased nitrification. Although gypsum is a useful litter amendment, it cannot be used to increase the liming ability of litter, despite the fact that gypsum‐amended litter has more CaCO3. Core Ideas: Calcium ions increase the rate of urea hydrolysis by poultry litter‐derived ureolytic isolates.Inoculating gypsum‐amended litter with ureolytic bacteria increases the CaCO3 and NH4+ content of litter.The soil liming potential of gypsum‐amended litter is not greater than the liming potential of unamended litter, even though treated litter contains more CaCO3. [ABSTRACT FROM AUTHOR]

During the summers of 2021 and 2022, we conducted a study in four Georgia Piedmont pastures to assess the effect of the presence of filth flies and epigeal arthropods on carbon and nitrogen emissions and soil nitrogen retention from lax rotational grazing systems under a legacy of low fertilization. Carbon dioxide (CO2), nitrous oxide (N2O), and ammonia (NH3) emissions were measured from dung on days 0, 4, 8, and 15 following depositions. Soil and manure samples were collected on days 0 and 16 and analyzed for ammonium (NH4+), nitrate (NO3−), plant-available nitrogen (PAN), and potentially mineralizable nitrogen (PMN). Manure samples were analyzed for total Kjeldahl nitrogen (TKN). The numbers of filth flies ovipositing and emerging from manure, fire ants, and epigeal arthropods around the manure were determined. Our results indicated that more than 12 ovipositing filth flies per manure pat can reduce PMN by up to 14.7 kg of nitrogen per hectare, while an increase in the biodiversity and abundance of predators may help to increase PAN and PMN in grazing systems, as well as decrease the number of emerging filth flies. [ABSTRACT FROM AUTHOR]

Introduction: Early life ethanol exposure is known to program hypothalamic proopiomelanocortin (POMC) neurons to express a reduced level of POMC and its control of stress axis functions throughout the life span. In this study, we tested whether miRNAs contribute to the ethanol-induced suppression of Pomc gene expression during the developmental period. Methods: In in vivo studies, POMC-EGFP male mice were fed with 2.5 g/kg ethanol using milk formula (AF), pair-fed isocaloric milk formula, or left in the litter during postnatal days (PNDs) 2–6. In in vitro studies, mHypoA-POMC/GFP cells were treated with ethanol (50 mM) for a 24-h period. Hypothalamic tissues or cell extracts were used for measurement of miRNAs and POMC mRNA. Results: Determination of genome-wide microRNA expression profile identified 40 miRNAs significantly altered in hypothalamic tissues of AF mice. In silico analysis further identified miRNA-383, -384, and -488 have putative binding sites at the POMC 3′UTR. However, only miR-383 and miR-384 are identified to be responsive to ethanol. Administration of miR-383 or -384 inhibitor oligos suppressed ethanol-stimulated miR-383 or -384 expression and restored Pomc mRNA and protein expression in AF mice. mHypoA-POMC/GFP cells when treated with ethanol showed elevated levels of miR-383 and miR-384 and reduced level of Pomc mRNA. Treatment with miR-383 or -384 mimic oligos reduced the level of Pomc mRNA, while treatment with miR-383 or -384 inhibitor oligos increased the level of Pomc mRNA. Reporter assay further confirms the binding specificity of miR-383 and miR-384 to Pomc 3'UTR. Conclusion: These data suggest that miR-383 and miR-384 suppress Pomc gene expression and may contribute to the ethanol-induced alteration of the stress axis functions. [ABSTRACT FROM AUTHOR]

The granular column collapse is a benchmark configuration for the study of granular flows in dry, saturated, and submerged conditions. The collapse sequence and resultant mobility is acknowledged to be controlled by the column aspect ratio, while grain properties define the relative transition of each stage. Grain shape effects are found to modify the global shear resistance of granular media, with a strong and coupled interaction when interacting with a fluid. In this work, we present the first steps towards the study of grain shape effects in a column collapse when interacting with an ambient fluid. For this purpose, we use a planar configuration and explore the collapse of a column consisting of rod-like grains and study the initial and after collapse grain orientations. On it, the mobilized grains deposit in a preferential horizontal orientation, but further experiments are required to confirm if a nematic configuration can be achieved.

As plant litter decomposes, its mass exponentially decreases until it reaches a non-zero asymptote. However, decomposition rates vary considerably among litter types as a function of their overall quality (i.e., carbon:nitrogen (C:N) ratio and litter chemistry). We investigated the effects of hairy vetch (HV: Vicia villosa Roth):cereal rye (RYE: Secale cereale L.) biomass proportions with or without broadcasted poultry manure on overall litter quality before and during decomposition. As HV biomass proportions increased from 0 to 100%, the relative susceptibility of HV:RYE mixtures to microbial decomposition increased due to: (i) decrease in the initial C:N ratio (87:1 to 10:1 in 2012 and 67:1 to 9:1 in 2013), (ii) increase in the non-structural labile carbohydrates (33 to 61% across years), and (iii) decrease in the structural holo-cellulose (59 to 33% across years) and lignin (8 to 6% across years) fractions. Broadcasted poultry manure decreased the overall initial quality of HV-dominated litters and increased the overall initial quality of RYE-dominated litters. Across all HV:RYE biomass proportions with or without poultry manure, chemical changes during litter decay were related to proportional mass loss. Therefore, the relative decrease in carbohydrates and the concomitant increase in holo-cellulose and lignin fractions were more pronounced for fast decomposing litter types, i.e., litters dominated by HV rather than RYE. While our results suggest possible convergence of litter C:N ratios, initial differences in litter chemistry neither converged nor diverged. Therefore, we conclude that the initial chemistry of litter before decomposition exerts a strong control on its chemical composition throughout the decay continuum. [ABSTRACT FROM AUTHOR]

Microbial communities have vital roles in systems essential to human health and agriculture, such as gut and soil microbiomes, and there is growing interest in engineering designer consortia for applications in biotechnology (e.g., personalized probiotics, bioproduction of high-value products, biosensing). The capacity to monitor and model metabolite exchange in dynamic microbial consortia can provide foundational information important to understand the community level behaviors that emerge, a requirement for building novel consortia. Where experimental approaches for monitoring metabolic exchange are technologically challenging, computational tools can enable greater access to the fate of both chemicals and microbes within a consortium. In this study, we developed an in-silico model of a synthetic microbial consortia of sucrose-secreting Synechococcus elongatus PCC 7942 and Escherichia coli W. Our model was built on the NUFEB framework for Individual-based Modeling (IbM) and optimized for biological accuracy using experimental data. We showed that the relative level of sucrose secretion regulates not only the steady-state support for heterotrophic biomass, but also the temporal dynamics of consortia growth. In order to determine the importance of spatial organization within the consortium, we fit a regression model to spatial data and used it to accurately predict colony fitness. We found that some of the critical parameters for fitness prediction were inter-colony distance, initial biomass, induction level, and distance from the center of the simulation volume. We anticipate that the synergy between experimental and computational approaches will improve our ability to design consortia with novel function. Author summary: Microbial communities, play important, yet poorly understood roles in health and agriculture. As we develop a better understanding of how these communities interact together, as well as with their host organisms, there is growing interest in engineering communities with specific functions, such as for treating disease, personalized probiotics, or aiding plants with nutrient uptake. To better understand how these microbes interact with each other, we want to monitor the exchange of metabolites and the locations of the microbes, tasks which at present are technically challenging, if not impossible. Where experimental approaches for monitoring metabolites are limited, computational tools can enable greater access to the fate of both chemicals and microbes within a community. In this study, we developed a computerized model of a synthetic microbial community of two bacteria, one which performs photosynthesis and supplies sugar and another which consumes the sugar for growth. We showed that the relative level of sugar secretion regulates not only the steady-state support for the consumer partner's growth, but also how the community changes with time. To determine the importance of spatial organization within the community, we fit a model and used it to predict colony growth. We anticipate that the synergy between experimental and computational approaches will improve our ability to design microbial communities with new functions. [ABSTRACT FROM AUTHOR]

Bacterial microcompartments (BMC) are complex macromolecular assemblies that participate in varied chemical processes in about one fourth of bacterial species. BMC-encapsulated enzymatic activities are segregated from other cell contents by means of semipermeable shells, justifying why BMC are viewed as prototype nano-reactors for biotechnological applications. Herein, we undertook a comparative study of bending propensities of BMC hexamers (BMC-H), the most abundant shell constituents. Published data show that some BMC-H, like β-carboxysomal CcmK, tend to assemble flat whereas other BMC-H often build curved objects. Inspection of available crystal structures presenting BMC-H in tiled arrangements permitted us to identify two major assembly modes with a striking connection with experimental trends. All-atom molecular dynamics (MD) supported that BMC-H bending is triggered robustly only from the arrangement adopted in crystals by BMC-H that experimentally form curved objects, leading to very similar arrangements to those found in structures of recomposed BMC shells. Simulations on triplets of planar-behaving hexamers, which were previously reconfigured to comply with such organization, confirmed that bending propensity is mostly defined by the precise lateral positioning of hexamers, rather than by BMC-H identity. Finally, an interfacial lysine was pinpointed as the most decisive residue in controlling PduA spontaneous curvature. Globally, results presented herein should contribute to improve our understanding of the variable mechanisms of biogenesis characterized for BMC, and of possible strategies to regulate BMC size and shape. Author summary: Bacterial microcompartments are complex macromolecular ensembles that participate in varied metabolic processes in many microorganisms. They consist of a proteinaceous shell that encapsulates enzymatic cargo that mediate connected chemical reactions. Being confined within shells, the overall efficiency of the process is thought to augment, and reactions that imply toxic intermediates, which are lethal to the host in free-diffusing context, become feasible. These natural nano-reactors are therefore appealing for biotechnology purposes. Understanding how such complex objects form is essential. Experimental studies demonstrated the existence of two possible pathways. Thus, shell components grew onto a preformed core of organized cargo in cyanobacterial carboxysomes, whereas in Pdu compartments, both cargo and shell formation seemed to occur randomly. With the aim to contribute to the understanding of the different biogenesis pathways, here we investigated the trend of the most abundant protein constituents of bacterial micro-compartment shells to form curved structures. We first discovered the occurrence of two major assembly modes in deposited BMC-H crystal structures that clustered proteins in two groups that correlate well to their experimental propensities to form bent or flat structures. Subsequently, molecular dynamic simulations supported that only one of the modes is ready to curve. Moreover, simulations on protein mutants pinpointed a residue that seems to be pivotal in triggering bending. Globally, our data permit to draw a scenario that explains BMC biogenesis differences as a result of the capture of some BMC-H, such as CcmK of carboxysomes, in local minima corresponding to flat states that would delay closure of BMC shells, something that might require the intervention of other molecular effectors. [ABSTRACT FROM AUTHOR]

The aim of this article is to explore the historical genealogy and the process by which social citizenship was constituted in Spain. Because its origins lie in nineteenth -century social reformism, the reasons why it appeared and the repercussions it had require analysis. This analysis clearly reveals that social reformism emerged as the result of the internal crisis of the imaginary of classical liberal individualism and its ensuing reframing in organicist terms. Given the incapacity of the liberal regime to attain the promised social, economic, and harmonious egalitarian political order, the new individualist organicism promoted the adoption of new ways of reaching this objective. The most important was the announcement of social reforms, which required state intervention in economic and labour relations. With time, these measures of reform would acquire the condition of social rights and give rise to the institution of so-called social citizenship. [ABSTRACT FROM AUTHOR]

Growers rely on nutrient sufficiency ranges (NSRs) after plant tissue analysis to inform timely nutrient management decisions. The NSRs are typically established from survey studies across multiple locations, which could be confounded by several abiotic and biotic factors. We conducted field studies in 2020, 2021, and 2022 to validate the lower thresholds of the NSRs for corn (Zea mays) at the early growth stage as reported in the Southern Cooperative Series Bulletin #394. We induced various corn nutritional levels by making different nutrient application rates. If the NSRs are valid, samples within the same replication that satisfy the NSRs of all nutrients should have similar biomass accumulation. The results showed that the NSRs were not valid under the conditions tested. In total, 47.6% of the samples satisfied all the lower thresholds of the NSRs, and 25.4% of those samples had relative biomass <50%, with relative biomass even as low as 24.2% observed. Moreover, 9.6% of the total samples had P and Cu levels that failed to meet the lower threshold but still had relative biomass ≥75%. The findings highlight the sensitivity of corn to nutrient imbalance and the need to optimize nutrient diagnostic methods at the early growth stage. [ABSTRACT FROM AUTHOR]

The recent explosion of interest and advances in machine learning technologies has opened the door to new analytical capabilities in microbiology. Using experimental data such as images or videos, machine learning, in particular deep learning with neural networks, can be harnessed to provide insights and predictions for microbial populations. This paper presents such an application in which a Recurrent Neural Network (RNN) was used to perform prediction of microbial growth for a population of two Pseudomonas aeruginosa mutants. The RNN was trained on videos that were acquired previously using fluorescence microscopy and microfluidics. Of the 20 frames thatmake up each video, 10 were used as inputs to the network which outputs a prediction for the next 10 frames of the video. The accuracy of the network was evaluated by comparing the predicted frames to the original frames, as well as population curves and the number and size of individual colonies extracted from these frames. Overall, the growth predictions are found to be accurate in metrics such as image comparison, colony size, and total population. Yet, limitations exist due to the scarcity of available and comparable data in the literature, indicating a need for more studies. Both the successes and challenges of our approach are discussed. [ABSTRACT FROM AUTHOR]

Currently, demand for functional foods is increasing in the public interest in order to improve life expectations and general health. Food matrices containing probiotic microorganisms and active compounds encapsulated into carrier agents are essential in this context. Encapsulation via the lyophilisation method is widely used because oxidation reactions that affect physicochemical and nutritional food properties are usually avoided. Encapsulated functional ingredients, such as quercetin and Bacillus clausii, using two carrier agents' matrices—I [inulin (IN), lactose (L) and maltodextrin (MX)] and II [arabic (A), guar (G), and xanthan (X) gums)]—are presented in this work. A D-optimal procedure involving 59 experiments was designed to evaluate each matrix's yield, viability, and antioxidant activity (AA). Matrix I (33.3 IN:33.3 L:33.3 MX) and matrix II (33.3 A:33.3 G:33.3 X) exhibited the best yield; viability of 9.7 log10 CFU/g and 9.73 log10 CFU/g was found in matrix I (using a ratio of 33.3 IN:33.3 L:33.3 MX) and matrix II (50 G:50 X), respectively. Results for the antioxidant capacity of matrix I (100 IN:0 L:0M X) and matrix II (0 A:50 G:50 X) were 58.75 and 55.54 (DPPH* scavenging activity (10 µg/mL)), respectively. Synergy between matrices I and II with use of 100IN:0L:OMX and 0A:50G:50X resulted in 55.4 log10 CFU/g viability values; the antioxidant capacity was 9. 52 (DPPH* scavenging activity (10 µg/mL). The present work proposes use of a carrier agent mixture to produce a functional ingredient with antioxidant and probiotic properties that exceed the minimum viability, 6.0 log10 CFU/g, recommended by the FAO/WHO (2002) to be probiotic, and that contributes to the recommended daily quercetin intake of 10–16 mg/day or inulin intake of 10–20 g/day and dietary fibre intake of 25–38 g per day. [ABSTRACT FROM AUTHOR]

Using density functional theory with an accurate treatment of van der Waals interactions, we investigate the enantioselective recognition and separation of chiral molecules on stepped metal surfaces. Our calculations demonstrate that the separation ability of metal substrates can be significantly enhanced by surface decoration and external strain. For example, applying 2% tensile strain to the Ag-alloyed Au(532) surface leads to a dramatic increase (by 89%) in cysteine enantioselectivity as compared to that of pristine Au(532). Analysis on the computed binding energies shows that the interaction energy is the predominant factor that affects the separation efficiency in strongly bound systems. Our study presents a new strategy to modify the enantioselectivity of stepped metal surfaces and paves the way for exploring high efficiency chiral separation technology in pharmaceutical industry. [ABSTRACT FROM AUTHOR]

The objective of this study was to assess the effectiveness of the blends with different levels of lactose-maltodextrin (8:5, 10:5, and 12:5 % w/v) during the spray-drying of the passion fruit juice. The drying was carried out in a laboratory spray dryer (Pulvis GB 22 model) at two inlet air temperatures (180 and 190 ºC), and two air pressures (0.10 and 0.20 MPa). The moisture content, hygroscopicity and vitamin C retention were evaluated in the powder obtained. Response surface plots (pO objectivo deste estudo foi a avaliação da efectividade das misturas en diferentes níveis de lactose-maltodextrina (8:5, 10:5, 12:5 % w/v) durante a pulverização do sumo de maracujá. A secagem foi feita em um atomizador de laboratório de pulverização (modelo Pulvis GB 22) com 2 entradas de temperatura de ar (180 e 190 ºC), e 2 compressores de pressão de ar (0.10 e 0.20 MPa). O índice da mistura, higroscopicidade e retenção de vitamina C foram avaliados no pó obtido. As curvas de superfície de resposta (p

Summary: The aim of this study was to evaluate the effect of combining techniques such as blanching time, pH and aw reduction on microbiological growth and enzymatic activity to increase the shelf life of fresh escamoles. A completely randomised factorial design with three factors (aw, pH and blanching time) and two different levels per factor was created to obtain the preservative conditions based on the microbiological growth and enzymatic activity of escamoles. The results indicated that the experimental conditions of aw, pH and blanching time were 0.90, 5 and 10 or 15 s, respectively, with reduced microbial growth and proteolytic activity, which allowed significantly increasing the escamoles' shelf life from 4 to 45 days under refrigeration at 4°C. Therefore, it is feasible to use this methodology for the preservation of this product in order to resemble fresh, microbiologically safe escamoles. [ABSTRACT FROM AUTHOR]

Understanding the influence of cattle grazing on soil carbon and bulk density during extreme dry to wet periods can help us design more resilient and sustainable grazing systems for low-input management scenarios. A study was conducted to evaluate changes in loss-on-ignition (LOI) carbon and bulk density (BD) in the top 20 cm soil layer when eight continuous grazing (CG) pastures were converted to either continuous grazing with hay distribution (CHD-4) or strategic grazing (STR-4). STR included lure management of cattle with movable-equipages, exclusion and over-seeding erosion-vulnerable areas, and a relaxed rotational grazing. Changes in relationships between cattle density (CD), LOI, and BD were evaluated for change in grazing management from 2015 to 2018. Reduction in LOI carbon (0–5, 5–10, 10–20 cm) and BD (5–10 cm) were observed in both CHD and STR pastures in 2018. CD in 2015 had either no relationship or a negative relationship on LOI while in 2018, CD positively influenced LOI in CHD (0–5 cm) and STR (0–5 and 5–10 cm) pastures. STR had lower BD with higher CD further away from concentrated flow paths mirroring cattle movement. Exclusions in the STR pastures had the greatest reduction in BD. Even with reduced carbon in the 0–5 cm soil layer the reduction in BD in the 5–10 cm soil layer helped build resilience in grazing systems that experience extreme weather events such as going from very dry to extensively wet. [ABSTRACT FROM AUTHOR]

The pile response is of great importance to the effectiveness of a row of piles used as a landslide mitigation method. However, the current classifications of the pile responses and failure modes do not consider the effects of soil displacement and the relative pile rigidity. An attempt is made in this paper to improve this using a non-dimensional model based on simplified ground consisted of two layers of cohesive soils. A hyperbolic p–y model is adopted to consider non-linear soil reactions. The calculations of three case histories show that the proposed model predicts the pile responses well. The dependencies for obtaining a pile response with maximum pile resistance have been identified and the influencing factors have been examined. The efficacy of the proposed approach has been demonstrated by the satisfactory result that it achieves in reproducing the more complex three-dimensional finite-element analyses. The application of the non-dimensional solutions indicates that it can increase the efficiency of the preliminary pile design. [ABSTRACT FROM AUTHOR]

Catchability (q) is a key parameter for the assessment and management of stocks because it is widely used to estimate other parameters such as fishing mortality and resource abundance. However, [...]