Urbana University

The correction factor (CF) is a crucial parameter in the back-calculation of drug consumption in wastewater-based epidemiology (WBE) studies. In this study, concentrations of 13 antidepressants and six metabolites were measured in wastewater samples for 11 consecutive months at the three largest treatment plants of Changshu, China. The monthly trends of mass loads and prescription volumes of the nine antidepressants widely detected in wastewater were largely parallel, indicating a strong correspondence between prescription and actual consumption during the study period. The correspondence yielded reliable CFs of target substances, among which the CF of norsertraline (14.5) was determined for the first time. The CFs based on excretion rates of venlafaxine and bupropion significantly overestimate consumption of the two drugs (by 76.5 and 82.4%, respectively), whereas the CF based on the excretion rate of N-desmethylcitalopram significantly underestimates its consumption (by 49.3%). The CFs of sertraline (16.4) and milnacipran (19.6) differ dramatically from those (500 and 1.8, respectively) based on excretion rates. The CFs used in previous studies would cause misleading pictures of regional mental health status and compromise the value of WBE. Therefore, the CFs derived here will play important roles in future studies as they yield a much more reliable estimation of consumption of major antidepressants.

Animal responses to fear cues are shaped by competing motivations such as hunger, access to mates and safety. In our previous work, wild mice (Apodemus spp.) showed little reaction to non-native predator scents. To test if native predator scents would elicit stronger reactions, we deployed fully enclosed laboratory chambers alongside a highly palatable food and olfactory cues from native foxes and cats and three types of controls, an herbivore scent (deer) and two procedural controls of wet and dry scent probes (the substrate on which we presented the scents) in the field. Despite using ontogenetically and evolutionarily relevant predator scents, mice showed no overt fear responses at any time, and only trivial behavioral differences between treatments. However, response variance was markedly higher for wet and dry controls compared to those exposed to animal-derived scents, suggesting a relatively greater perception of safety in chambers without scents. Collectively, these findings indicate that increased motivation for food and shelter during winter months buffered measurable responses to native predator scents. We conclude that the interpretation of risk sensitive behavior under natural conditions must account for ecological context, including shelter and food resources embedded within experimental assays, as well as seasonal tradeoffs associated with foraging decisions.

Land carbon sinks are responsible for removing about a quarter of anthropogenic CO$_2$ emissions, and make up approximately half of total global carbon sinks. Uncertainty in the response of land carbon sinks to climate and increasing CO$_2$ emissions are large, and dominate the uncertainty in total carbon sinks over the next century. Understanding the carbon cycle response to net-zero and net-negative emissions has important implications for projecting future climate. Experiments in the `flat10' model intercomparison (flat10MIP) were designed for directly estimating key climate metrics that underlie carbon budgeting frameworks. Here we characterize the response of land carbon pools and fluxes from ten emissions-driven Earth system models (ESMs) under positive, net-zero, and net-negative CO$_2$ emissions. Although there are many differences in simulated land carbon pools and fluxes across models, we find some consistent behavior across ESMs. 1) During the positive emissions phase, carbon is gained on land -primarily in vegetation pools- in both the tropics and mid-latitudes. 2) Following net-negative emissions to the point of cumulative zero emissions, vegetation carbon is lost from land. 3) In tropical latitudes, total carbon is lost coming primarily from vegetation pools, but in mid-latitudes nearly all models show net land carbon gain, primarily in soil pools. 4) Following an extended period of net-zero emissions, a majority of models again show carbon gain in mid-latitudes and vegetation carbon loss in the tropics. Under net-negative emissions the timing of vegetation carbon response relative to peak emissions is relatively consistent across ESMs, but timing of soil carbon response varies widely, implying larger intermodel disagreement associated with the longer timescale responses of land carbon.

Feruloyl esterase produced by certain microorganisms can help breakdown plant fiber. We investigated effects of inoculating feruloyl esterase-producing lactic acid bacteria (FLAB) in alfalfa silage on production performance and blood and liver markers of inflammation and oxidative stress in lactating dairy goats. Alfalfa was ensiled for 1 mo without additive (control, CON), with Limosilactobacillus reuteri YM13 without feruloyl esterase activity (YM13), or with a feruloyl esterase-producing L. reuteri A4-2 (A4-2). Forty-two dairy goats (53 ± 4 DIM; 37.2 ± 2.3 BW) were randomly assigned to 1 of 3 dietary treatments (n = 14/treatment) prepared with the above alfalfa silages and fed during 60 d. Silage and composite samples (concentrate + silage) were taken weekly. Jugular vein blood samples were taken on d 20, 40, and 60 before the morning feeding. Dairy goats were milked 2 × per day and milk samples taken on d 58 to 60. Five dairy goats from each group were slaughtered at the end of the experiment, and liver tissue samples collected for real-time quantitative PCR (RT-qPCR) assay. Serum antioxidant activity on d 20, 40, and 60, and production data were analyzed with PROC MIXED (SPSS 21.0, SPSS, Inc., Chicago, IL, United States). Biochemical indicators in silage and composite feed, and serum cytokine, immunoglobulin, biochemical indicators, and liver RT-qPCR in samples harvested on d 60 were analyzed using one-way ANOVA (SPSS 21.0, SPSS, Inc., Chicago, IL, United States). Compared with CON and YM13, inoculating with L. reuteri A4-2 led to lower silage pH and aNDF, but greater concentrations of lactic acid and ferulic acid along with activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and total antioxidant capacity (T-AOC). Feeding A4-2 inoculated alfalfa silage did not alter dry matter intake, milk yield, or feed efficiency. Dairy goats fed A4-2 had greater serum total antioxidant activity, and lower pro-inflammatory cytokine concentrations at 60 d. Furthermore, greater total protein, albumin, and immunoglobulin M (IgM), and lower alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase in serum were also observed in response to feeding A4-2. Compared with CON and YM13, overall mRNA abundance of the nuclear factor-E2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway genes NFE2L2, HMOX1, NQO1, SOD2, CAT, GPX1, GPX2, and GSR was greater in the liver of goats fed A4-2. In contrast, relative to CON and YM13 groups, feeding A4-2 resulted in an overall downregulation of KEAP1 and the nuclear factor kappa-B (NF-κB) signaling pathway-related genes NFKB1, RELA, NOX4, TNF, and IFNG. Overall, feruloyl esterase-producing lactic acid bacteria used as silage inoculant can confer potential health benefits without affecting production performance. Further studies to determine the specific mechanisms controlling these responses are warranted.

<strong class="journal-contentHeaderColor">Abstract.</strong> Aerosol-cloud interactions remain a large source of uncertainty in global climate models (GCMs) due to complex, nonlinear processes that alter aerosol properties and the inability to represent the full compositional complexity of aerosol populations within large-scale modeling frameworks. The spatial resolution of GCMs is often coarser than the scale of the spatially varying emissions in the modeled geographic region. This results in diffuse, uniform concentration fields of primary aerosol and gas-phase species instead of spatially heterogeneous concentrations. Aerosol processes such as gas-particle partitioning and coagulation are concentration-dependent in a non-linear manner, and thus the representation of spatially heterogeneous emissions impacts aerosol aging and properties. This includes climate-relevant quantities key to aerosol-cloud interactions including particle hygroscopicity and cloud condensation nuclei (CCN) activity. We investigate the impact of emissions spatial heterogeneity on aerosol properties including CCN activity via a series of first-of-a-kind particle-resolved large-eddy simulations with the modeling framework WRF-PartMC-MOSAIC-LES. CCN concentrations within the planetary boundary layer (PBL) are compared across numerous scenarios ranging in emissions spatial heterogeneity. CCN concentrations at low supersaturations (S_env = 0.1&ndash;0.3 %) increase in the upper PBL by up to 25 % for emissions scenarios with high spatial heterogeneity when compared to a uniform emissions base case. Process level analysis indicates that this increase is due to enhanced nitrate formation among scenarios with high emissions spatial heterogeneity.

Long-term application of phosphorus (P) fertilizers in the intensive croplands has led to the accumulation of residual phosphorus in soils, referred to as legacy phosphorus. Most reported observations on the role of extracellular polymeric substances in enhancing P availability have been based on microbially excreted mixtures, rather than on relatively pure exopolysaccharides, as used in the present study. The objective of this work was to investigate the effects of purified exopolysaccharides (EPS) produced from Rhizobium tropici on the solubility of soil legacy phosphorus and on their interactions with soil, clay minerals, and Fe/Al oxides. A Mississippi River Delta agricultural soil, two clay minerals (montmorillonite and kaolinite), and Fe/Al oxides were spiked with phosphate and treated with the purified EPS and then incubated under laboratory conditions at a field capacity moisture. Results show that EPS strongly interacted with phosphate, enhancing its complexation and promoting the solubilization of legacy soil phosphorus. EPS facilitated P transformation from the soil residual phosphorus fraction and HCl-extractable P (Ca–P) fractions into the water-soluble form, thereby increasing phosphorus bioavailability. Therefore, the current study demonstrates the beneficial role of EPS from Rhizobium tropici in improving the solubility and bioavailability of soil legacy phosphorus in agricultural soils where substantial phosphorus has accumulated, particularly in intensive cultivated crop fields. Application of EPS may therefore increase P fertilizer efficiency, reduce phosphorus losses through runoff, and mitigate water body eutrophication.

Abstract We consider a class of multi-agent distributed synchronization systems, which are modeled as n particles moving on the real line. This class generalizes the model of a multi-server queueing system, considered in Stolyar (Stoch. Syst. 12:340–372, 2022), employing so-called cancel-on-completion (c.o.c.) redundancy mechanism, but is motivated by other applications as well. In the multi-server queueing system a particle location represents a server workload. Under c.o.c. mechanism, when a job of class j arrives, it selects $$d_j$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>d</mml:mi> <mml:mi>j</mml:mi> </mml:msub> </mml:math> particles uniformly at random, which try to jump forward, by random distances, but their advance is truncated at the new location of the $$k_j$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>k</mml:mi> <mml:mi>j</mml:mi> </mml:msub> </mml:math> -th left-most selected particle ( $$k_j \le d_j$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msub> <mml:mi>k</mml:mi> <mml:mi>j</mml:mi> </mml:msub> <mml:mo>≤</mml:mo> <mml:msub> <mml:mi>d</mml:mi> <mml:mi>j</mml:mi> </mml:msub> </mml:mrow> </mml:math> ). Between jumps all particles move to the left at constant speed, but cannot cross point 0 (workload cannot be less than 0). Thus, the multi-server queueing system is modeled as a particle system, regulated at the left boundary point. The more general model of this paper is such that particles evolve the same way as the in left-regulated system, but we allow regulation boundaries on either side, or both sides, or no regulation at all. We consider the mean-field asymptotic regime, when the number of particles n and the job arrival rates go to infinity, while the job arrival rates per particle remain constant. The system state for a given n is the empirical distribution of the particles’ locations. Our results include: the existence/uniqueness of fixed points of mean-field limits (ML), which describe the limiting dynamics of the system; conditions for the steady-state asymptotic independence (concentration, as $$n \rightarrow \infty $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>n</mml:mi> <mml:mo>→</mml:mo> <mml:mi>∞</mml:mi> </mml:mrow> </mml:math> , of the stationary distribution on a single state, which is necessarily an ML fixed point); the limits, as $$n \rightarrow \infty $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>n</mml:mi> <mml:mo>→</mml:mo> <mml:mi>∞</mml:mi> </mml:mrow> </mml:math> , of the average velocity at which unregulated (free) particle system advances. In particular, our results for the left-regulated system unify and generalize the corresponding results in Stolyar (Stoch. Syst. 12:340–372, 2022). Our technical development is such that the systems with different types of regulation are analyzed within a unified framework. In particular, these systems are used as tools for analysis of each other.