Changes In Growth Rate Research Articles

Assessing the Impact of COVID-19 Prevention Measures on Adolescent Growth in Italy.

COVID-19 infection has caused increased morbidity and mortality worldwide. Several strategies have been adopted around the world to prevent its spread. Italy underwent a long lockdown for face-to-face educational activities, which were replaced with online classes. This longitudinal study aimed to analyze the effects of COVID-19 prevention measures on physical growth and body image perception in a sample of Italian adolescents who experienced the pandemic-induced lockdown in 2020. In particular, we wished to ascertain how lifestyle changes had affected their growth rates and health. Special attention was paid to increases in adiposity indicators (BMI, waist circumference, waist-to-height ratio) and weight caused by reduced physical activity, and consequent possible dissatisfaction with body image. We assessed the impact of school closures by comparing the annual growth rate and body image perception changes of adolescents (n = 60; age = 11.3 ± 0.4 years) who experienced this isolation with those in the following years who did not experience these restrictions (n = 68; age = 11.4 ± 0.3 years). As a consequence of the lockdown, our results indicate a greater annual growth rate in weight and other indices of adiposity (p < 0.05). As the virus is continuing to evolve and propagate, larger population studies can verify and confirm our findings. In promoting health policy to prevent the ongoing prevalence of obesity in adolescents, an accurate assessment of whether the increase in obesity rates during the pandemic is to be considered a temporary trend is highly recommended.

Growth Priorities of the Four Riverine Cyprinids during Early Ontogeny.

Growth patterns during early development of four species of riverine cyprinids, common dace (Leuciscus leuciscus L.), ide (Leuciscus idus L.), chub (Squalius cephalus L.) and common barbel (Barbus barbus L.), over 30 days of rearing, were analyzed. The study period covered three successive phases of larval development (preflexion, flexion, postflexion) and part of the juvenile development. The growth analysis carried out in the present study shows that significant allometric growth occurred mainly in preferentially localized body parts (head and tail) and was also associated with an increase in body height. The replacement of temporary structures (e.g., fin fold absorption) and the appearance of definitive structures around 21 mm TL (beginning of the juvenile period) corresponds to a stabilization of the relative growth of most parts of the body. This is probably due to the fact that the studied species had completed the most important part of the remodeling process (metamorphosis) and had achieved a body shape that allows juveniles to colonize faster water habitats. The results also indicate that individuals of species that are less developmentally advanced at the time of hatching (common barbel, chub) show greater initial dynamics of change in growth rate than individuals of species whose individuals are more advanced in ontogeny (common dace, ide). In addition, the small differences observed in growth parameters between successive periods analyzed, supported by the results of previous studies on these species, probably reflect the lack of abrupt changes in the behavior and habitat of the species studied.

Multiplex CRISPR editing of wood for sustainable fiber production.

The domestication of forest trees for a more sustainable fiber bioeconomy has long been hindered by the complexity and plasticity of lignin, a biopolymer in wood that is recalcitrant to chemical and enzymatic degradation. Here, we show that multiplex CRISPR editing enables precise woody feedstock design for combinatorial improvement of lignin composition and wood properties. By assessing every possible combination of 69,123 multigenic editing strategies for 21 lignin biosynthesis genes, we deduced seven different genome editing strategies targeting the concurrent alteration of up to six genes and produced 174 edited poplar variants. CRISPR editing increased the wood carbohydrate-to-lignin ratio up to 228% that of wild type, leading to more-efficient fiber pulping. The edited wood alleviates a major fiber-production bottleneck regardless of changes in tree growth rate and could bring unprecedented operational efficiencies, bioeconomic opportunities, and environmental benefits.

Evaluating the importance of individual heterogeneity in reproduction to Weddell seal population dynamics using integral projection models.

Identifying and accounting for unobserved individual heterogeneity in vital rates in demographic models is important for estimating population-level vital rates and identifying diverse life-history strategies, but much less is known about how this individual heterogeneity influences population dynamics. We aimed to understand how the distribution of individual heterogeneity in reproductive and survival rates influenced population dynamics using vital rates from a Weddell seal population by altering the distribution of individual heterogeneity in reproduction, which also altered the distribution of individual survival rates through the incorporation of our estimate of the correlation between the two rates and assessing resulting changes in population growth. We constructed an integral projection model (IPM) structured by age and reproductive state using estimates of vital rates for a long-lived mammal that has recently been shown to exhibit large individual heterogeneity in reproduction. Using output from the IPM, we evaluated how population dynamics changed with different underlying distributions of unobserved individual heterogeneity in reproduction. Results indicate that the changes to the underlying distribution of individual heterogeneity in reproduction cause very small changes in the population growth rate and other population metrics. The largest difference in the estimated population growth rate resulting from changes to the underlying distribution of individual heterogeneity was less than 1%. Our work highlights the differing importance of individual heterogeneity at the population level compared to the individual level. Although individual heterogeneity in reproduction may result in large differences in the lifetime fitness of individuals, changing the proportion of above- or below-average breeders in the population results in much smaller differences in annual population growth rate. For a long-lived mammal with stable and high adult-survival that gives birth to a single offspring, individual heterogeneity in reproduction has a limited effect on population dynamics. We posit that the limited effect of individual heterogeneity on population dynamics may be due to canalization of life-history traits.

Anti-Fusarium activity of essential oil distilled from artemisinin (Artemisia annua L.) extraction residues

Fusarium, a major phytopathogen damages field crops causing huge losses to agriculture. This study evaluated the anti-Fusarium effects of essential oil distilled from artemisinin extraction residues (EOAR). The chemical composition of EOAR was analyzed and its growth inhibition effect was examined against four Fusarium species. The underlying molecular mechanism was uncovered by studying the changes in growth rate, mycelial morphology, biomolecular leakage, electrical conductivity, and transcriptome of the fungi. The results indicated that the main components of EOAR (such as camphor, borneol, etc.) significantly inhibited the growth of Fusarium by destroying the morphology and structure of cytomembrane, and promoting the leakage of intracellular biomolecules. Transcriptome analysis showed that the differentially expressed genes after treatment with EOAR were mainly related to the transmembrane transport pathway and activity, carbon metabolism, and ribosome function of F. graminearum. Our findings suggest that oily waste from Artemisia annua after extraction of artemisinin can be recycled for the production of EOAR, which can be a potential green and effective fungicide against Fusarium.

Revisiting soil microbial biomass: Considering changes in composition with growth rate

Soil microbial biomass is assumed to have stable chemical composition. Various components of the biomass such as DNA, ATP, or chloroform-labile organic carbon are measured in soil and converted into total microbial biomass using experimentally derived conversion factors, which are also assumed to be constant. However, several observations suggest the opposite. The composition of soil microbial biomass is likely changing with specific growth rate as observed in pure cultures of single microbial species. In this study, we define a “sub-Microbial” model that explicitly represents changes in composition of soil microbial biomass associated with changes in specific growth rate. We calibrate the model with published data and compare its performance with the simpler Monod and Pirt models, which consider microbial biomass as a single pool with invariant chemical composition. The model explains well the variability in chloroform-labile content of microbial biomass following organic substrate additions as well as variability in ratios of different components of microbial biomass. Changes in composition of soil microbial biomass are quantitatively significant and occur over hours and days resulting in our sub-Microbial model outperforming both the Monod and Pirt models. Our results further indicate that the composition of soil microbial biomass changes consistently with growth rate across various soils. Here, we provide a methodological recommendation how to determine total soil microbial biomass and its physiological characteristics such as growth rate, turnover rate and substrate use efficiency as accurately as possible. In light of the presented results, we would like to initiate a discussion about the methodological issues associated with measurement of soil microbial biomass as these measurements are expected to inform a new generation of microbially-explicit soil biogeochemical models predicting development of terrestrial ecosystems under various scenarios.

Engineering the Metabolic Profile of Clostridium cellulolyticum with Genomic DNA Libraries

Clostridium cellulolyticum H10 (ATCC 35319) has the ability to ferment cellulosic substrates into ethanol and weak acids. The growth and alcohol production rates of the wild-type organism are low and, therefore, targets of metabolic engineering. A genomic DNA expression library was produced by a novel application of degenerate oligonucleotide primed PCR (DOP-PCR) and was serially enriched in C. cellulolyticum grown on cellobiose in effort to produce fast-growing and productive strains. The DNA library produced from DOP-PCR contained gene-sized DNA fragments from the C. cellulolyticum genome and from the metagenome of a stream bank soil sample. The resulting enrichment yielded a conserved phage structural protein fragment (part of Ccel_2823) from the C. cellulolyticum genome that, when overexpressed alone, enabled the organism to increase the ethanol yield by 250% compared to the plasmid control strain. The engineered strain showed a reduced production of lactate and a 250% increased yield of secreted pyruvate. Significant changes in growth rate were not seen in this engineered strain, and it is possible that the enriched protein fragment may be combined with the existing rational metabolic engineering strategies to yield further high-performing cellulolytic strains.

Salinity Impacts on Floc Size and Growth Rate With and Without Natural Organic Matter

AbstractDue to the flocculation process, suspended mud aggregates carried by rivers to the coastal ocean are thought to undergo changes in size and shape in response to environmental drivers such as turbulence, sediment concentration, organic matter (OM), and salinity. Some have assumed that salt is necessary for floc formation, and that mud, therefore, reaches the estuary unflocculated. Yet mud flocs exist in freshwater systems long before the estuarine zone, likely due to the presence of OM acting as a floc‐promoting binder. Therefore, it is important to consider how salinity affects flocculation, if at all, in the presence of OM. Here, we used experiments to examine the flocculation of a natural mud with and without OM. Results showed that the rate of floc growth and equilibrium size both increase with salinity regardless of the presence or absence of OM. However, the response of both to salinity was stronger when OM was present. In deionized water, natural sediment with OM was seen to produce large flocs. However, the size distribution of the suspension tended to be bimodal. With the addition of salt, increasing amounts of unflocculated material became bound within flocs, producing a more unimodal size distribution. Here, the enhancing effects of salt were noticeable at even 0.5 ppt, and increases in salinity past 3–5 ppt only marginally increased the floc growth rate and final size. Data from the experiment were used to develop a salinity‐dependent model to account for changes in floc growth rate and equilibrium size.

Removal of mercury by silica-supported ionic liquids: Efficiency and ecotoxicological assessment

Anthropogenic impacts have affected the coastal environment and contributed to its contamination. Mercury (Hg) is widespread in nature and has been shown to be toxic in even the smallest amounts, negatively affecting not only the marine ecosystem but also the entire trophic chain due to its biomagnification. Mercury ranks third on the Agency for Toxic Substances and Diseases Registry (ATSDR) priority list and it is therefore imperative to develop more effective methods than those currently available to avoid the persistence of this contaminant in aquatic ecosystems. The present study aimed to evaluate the effectiveness of six different silica-supported ionic liquids (SIL) in removing Hg from contaminated saline water, under realistic conditions ([Hg] = 50 µg/L), and to ecotoxicologically evaluate the safety of the SIL-remedied water, using as test model the marine macroalga Ulva lactuca. The results revealed that SIL [Si][C3C1im][SCN] (250 mg/L) was the most effective in removing Hg from solution, with a efficiency up to 99 % in just 6 h, that enable to obtain < 1 µg/L Hg (European guideline in drinking water). U. lactuca exposed to either the SIL and/or the remedied water showed no significant changes in relative growth rate and chlorophyll a and b levels, compared to the control condition. Biomarker analysis (LPO, GSH, GSSG, SOD, GPx, CAT and GRed) also showed no significant changes in the biochemical performance of U. lactuca. Therefore, it could be assumed that water treatment with SIL or its presence in an aqueous environment does not pose toxicity levels that could inhibit the metabolism or cause cell damage to U. lactuca.

Mathematical properties of optimal fluxes in cellular reaction networks at balanced growth.

The physiology of biological cells evolved under physical and chemical constraints, such as mass conservation across the network of biochemical reactions, nonlinear reaction kinetics, and limits on cell density. For unicellular organisms, the fitness that governs this evolution is mainly determined by the balanced cellular growth rate. We previously introduced growth balance analysis (GBA) as a general framework to model and analyze such nonlinear systems, revealing important analytical properties of optimal balanced growth states. It has been shown that at optimality, only a minimal subset of reactions can have nonzero flux. However, no general principles have been established to determine if a specific reaction is active at optimality. Here, we extend the GBA framework to study the optimality of each biochemical reaction, and we identify the mathematical conditions determining whether a reaction is active or not at optimal growth in a given environment. We reformulate the mathematical problem in terms of a minimal number of dimensionless variables and use the Karush-Kuhn-Tucker (KKT) conditions to identify fundamental principles of optimal resource allocation in GBA models of any size and complexity. Our approach helps to identify from first principles the economic values of biochemical reactions, expressed as marginal changes in cellular growth rate; these economic values can be related to the costs and benefits of proteome allocation into the reactions' catalysts. Our formulation also generalizes the concepts of Metabolic Control Analysis to models of growing cells. We show how the extended GBA framework unifies and extends previous approaches of cellular modeling and analysis, putting forward a program to analyze cellular growth through the stationarity conditions of a Lagrangian function. GBA thereby provides a general theoretical toolbox for the study of fundamental mathematical properties of balanced cellular growth.

Cultivation of blue green algae (Arthrospira platensis Gomont, 1892) in wastewater for biodiesel production

The production of biodiesel has become an important issue in the effort to reduce gas emissions due to the climate change crisis; therefore, algae have widely used to produce biodiesel for energy sustainability. The present study represented an effort to assess the ability of the alga Arthrospira platensis to produce fatty acids involved in biofuel (diesel) by cultivation in Zarrouk media enriched with different municipal wastewater concentrations. Wastewater was used in different concentrations (5, 15, 25, 35 and 100% [control]). Five fatty acids from the alga were determined and included in the present study. These were inoleic acid, palmitic acid, oleic acid, gamma-linolenic acid, and docosahexaenoic acid. Impact of different cultivation conditions were studied in terms of observed changes in growth rate, doubling time, total carbohydrate, total protein, chlorophyll a, carotenoids, phycocyanin, allophycocyanin, and phycobiliproteins. Results showed an increase in the values of growth rate, total protein content, chlorophyll a, and levels of carotenoids at all treatments except for carbohydrate content, which decreased with an increasing concentration of wastewater. The high value of doubling time (11.605 days) was recorded at treatment 5%. Fatty acids yields were increased at treatment 5% and 15%. The highest concentrations of fatty acids were 3.108 mg/g for oleic acid, gamma-linolenic acid (28.401 mg/g), docosahexaenoic acid (41.707 mg/g), palmitic acid (1.305 mg/g), and linoleic acid (0.296 mg/g). Moreover, the range of phycocyanin (0.017–0.084 mg/l), allophycocyanin (0.023–0.095 mg/l), and phycobiliproteins (0.041–0.180 mg/l) were obtained in treatment with 15–100%, respectively. Cultivation with municipal wastewater reduced the values of nitrate, phosphate, and electrical conductivity as well as increased dissolved oxygen. Maximum electrical conductivity was recorded in untreated wastewater with algae, while the highest level of dissolved oxygen was noted at 35% concentration. The use of the household wastewater is more environmentally friendly as an alternative of the traditional cultivation techniques used for long-term for biofuel production.

Ontogenetic progression of individual head size in the larvae of the beetle Trypoxylus dichotomus (Coleoptera: Scarabaeidae): catch-up growth within stages and per-stage growth rate changes across stages.

The ontogenetic progression of insect larval head size has received much attention due to its fundamental and practical importance. However, although previous studies have analyzed the population mean head size, such an approach may not be appropriate for developmental studies of larval head sizes when the trajectory of individual head size growth is correlated with pre-molt head size and developmental stage. Additionally, there is covariation between the head and body sizes; however, few studies have compared the ontogenetic progression of individual head sizes with that of individual body sizes. In this investigation, the per-stage growth rates (PSGRs) for head width (HW) and cubic-rooted body mass at the beginning of each instar (body size, BS) were assessed in Trypoxylus dichotomus. Linear models were used to test the size- and instar-dependence of the ontogenetic progression of individual HW and BS. The individual PSGRs of the HW (iPSGRH) and BS (iPSGRB) were then compared. In addition, the allometric relationship between HW and BS was examined. The iPSGRH was negatively correlated with the pre-molt HW at every instar (i.e., head catch-up growth). Furthermore, the mean iPSGRH at L2 was relatively higher than that at L1 when the pre-molt HW was used as covariate in the analysis (i.e., instar-effect), whereas the mean iPSGRH decreased ontogenetically. The iPSGRB showed catch-up growth and instar-effects similar to those of iPSGRH; however, iPSGRH was found to be lower than iPSGRB. Due to the differences between the PSGRs for the larval head and body, the larval head size showed negative ontogenetic allometry against body size.

From a different angle: genetic diversity underlies differentiation of waterlogging-induced epinasty in tomato.

In tomato, downward leaf bending is a morphological adaptation towards waterlogging, which has been shown to induce a range of metabolic and hormonal changes. This kind of functional trait is often the result of a complex interplay of regulatory processes starting at the gene level, gated through a plethora of signaling cascades and modulated by environmental cues. Through phenotypical screening of a population of 54 tomato accessions in a Genome Wide Association Study (GWAS), we have identified target genes potentially involved in plant growth and survival during waterlogging and subsequent recovery. Changes in both plant growth rate and epinastic descriptors revealed several associations to genes possibly supporting metabolic activity in low oxygen conditions in the root zone. In addition to this general reprogramming, some of the targets were specifically associated to leaf angle dynamics, indicating these genes might play a role in the induction, maintenance or recovery of differential petiole elongation in tomato during waterlogging.

Dynamic effect of economic growth on the persistence of suicide rates

Positive and negative economic growth is closely related to the suicide rate. To answer the question whether economic development has a dynamic impact on this rate, we used a panel smooth transition autoregressive model to evaluate the threshold effect of economic growth rate on the persistence of suicide. The research period was from 1994 to 2020, and the results show that the suicide rate had a persistent effect, which varied over time depending on the transition variable within different threshold intervals. However, the persistent effect was manifested in different degrees with the change in the economic growth rate and as the lag period of the suicide rate increased, the effect of the influence gradually decreased. We investigated different lag periods and noted that the impact on the suicide rate was the strongest in the first year after an economic change and then reduced to be only marginal after three years. This means that the growth momentum of the suicide rate within the first two years after a change in the economic growth rate, should be included in policy considerations of how to prevent suicides.

Linear instabilities in the hot-ion regime in a high-field spherical tokamak

The present operating high-field compact spherical tokamak ST40 is an important step toward an ST-based fusion reactor (Gryaznevich and Asunta 2017 Fusion Eng. Des. 123 177; McNamara 2023 Nucl. Fusion 63 054002). Temperature and density profiles and their uncertainties in recent hot ion ST40 plasmas with central ion temperatures exceeding 8.6 keV, have been inferred using an integrated analysis of several diagnostics including line-of-sight integration and volume average measurements, as well as limited profile information from a charge-exchange-recombination spectrometer. A linear gyrokinetic stability analysis has been carried out to identify the most unstable micro-instabilities in these hot ion plasmas. In one of these plasmas, it is found that linear growth rates of both ion- and electron-scale ( where k θ is the poloidal wavenumber and ρ s is the ion gyro-radius with sound speed) modes decrease from the edge toward the core of the plasma (i.e. from ρ = 0.8 to 0.3 where ρ is the square root of the normalized magnetic flux), while the change of linear growth rates at is non-monotonic. In particular, at ρ = 0.3 no unstable mode was found at , and about an order of magnitude reduction in the maximum linear growth rate in the ion-scale wavenumber range of is seen at ρ = 0.3 compared with the ρ = 0.8 location. It is found through parametric scans that while the ion temperature gradient (ITG) mode/trapped electron mode (TEM) and kinetic ballooning mode (KBM)/kinetic shear Alfvén (KSA) mode are more important in the plasma core, ubiquitous mode (UM) is found to be the important ion-scale instability at . At ρ = 0.8, two instabilities are found at the electron scale, with one being the typical electrostatic electron temperature gradient (ETG) mode at ρ e scale and beyond and the other being an unidentified low-real-frequency instability (at the intermediate scale between electron and ion gyroradii) which can propagate in the ion direction and is driven by ETG. The existence of UM at the ion scale and the low-real-frequency instability and ETG mode at the electron scale at ρ = 0.8 is supported by an extensive linear gyrokinetic stability analysis of another ST40 hot ion plasma in a wider parametric range, taking into account the uncertainties in the experimental profiles.

Estimating Wolf Population Size and Dynamics by Field Monitoring and Demographic Models: Implications for Management and Conservation.

We estimated the current size and dynamics of the wolf population in Tuscany and investigated the trends and demographic drivers of population changes. Estimates were obtained by two different approaches: (i) mixed-technique field monitoring (from 2014 to 2016) that found the minimum observed pack number and estimated population size, and (ii) an individual-based model (run by Vortex software v. 10.3.8.0) with demographic inputs derived from a local intensive study area and historic data on population size. Field monitoring showed a minimum population size of 558 wolves (SE = 12.005) in 2016, with a density of 2.74 individuals/100 km2. The population model described an increasing trend with an average annual rate of increase λ = 1.075 (SE = 0.014), an estimated population size of about 882 individuals (SE = 9.397) in 2016, and a density of 4.29 wolves/100 km2. Previously published estimates of wolf population were as low as 56.2% compared to our field monitoring estimation and 34.6% in comparison to our model estimation. We conducted sensitivity tests to analyze the key parameters driving population changes based on juvenile and adult mortality rates, female breeding success, and litter size. Mortality rates played a major role in determining intrinsic growth rate changes, with adult mortality accounting for 62.5% of the total variance explained by the four parameters. Juvenile mortality was responsible for 35.8% of the variance, while female breeding success and litter size had weak or negligible effects. We concluded that reliable estimates of population abundance and a deeper understanding of the role of different demographic parameters in determining population dynamics are crucial to define and carry out appropriate conservation and management strategies to address human-wildlife conflicts.

Identification and Characterization of Dmct: A Cation Transporter in Yarrowia lipolytica Involved in Metal Tolerance

Yarrowia lipolytica is a dimorphic fungus used as a model organism to investigate diverse biotechnological and biological processes, such as cell differentiation, heterologous protein production, and bioremediation strategies. However, little is known about the biological processes responsible for cation concentration homeostasis. Metals play pivotal roles in critical biochemical processes, and some are toxic at unbalanced intracellular concentrations. Membrane transport proteins control intracellular cation concentrations. Analysis of the Y. lipolytica genome revealed a characteristic functional domain of the cation efflux protein family, i.e., YALI0F19734g, which encodes YALI0F19734p (a putative Yl-Dmct protein), which is related to divalent metal cation tolerance. We report the in silico analysis of the putative Yl-Dmct protein’s characteristics and the phenotypic response to divalent cations (Ca2+, Cu2+, Fe2+, and Zn2+) in the presence of mutant strains, Δdmct and Rdmct, constructed by deletion and reinsertion of the DMCT gene, respectively. The absence of the Yl-Dmct protein induces cellular and growth rate changes, as well as dimorphism differences, when calcium, copper, iron, and zinc are added to the cultured medium. Interestingly, the parental and mutant strains were able to internalize the ions. Our results suggest that the protein encoded by the DMCT gene is involved in cell development and cation homeostasis in Y. lipolytica.

The Fluctuation Characteristics and Periodic Patterns of Potato Prices in China

The aim of this paper was to provide a more scientific and effective analysis of the fluctuation pattern of the Chinese potato market by extracting the characteristics of the price fluctuation cycle to effectively grasp the characteristics of price changes in the potato market, thus promoting the stable and healthy development of the Chinese potato industry, and to expand the application scenarios of the EEMD model to provide a reference for the study of price fluctuation patterns in other agricultural markets. This study used an ensemble empirical modal decomposition (EEMD) model to examine time-series data on Chinese wholesale potato market prices from January 2005 to December 2021. The results showed that (1) Chinese wholesale potato market prices are characterized by some rigidity, with sharp changes in growth rates; (2) Chinese wholesale potato market prices are dominated by short- and medium-term fluctuations, and the decomposed components can better reflect the characteristics of the original series fluctuations; (3) Chinese wholesale potato market monthly prices have long- and short-term fluctuations with a 6- and 19-month cycle, and are dominated by short-term high-frequency fluctuations; (4) monthly price fluctuations in the Chinese wholesale potato market are more intense in high-frequency than low-frequency fluctuations, and there is a strong correlation between high- and low-frequency fluctuations in precipitation, temperature and potato prices. Finally, suggestions were made for creating and improving a national potato price information platform and strengthening the information early warning mechanism; improving the potato production interest linkage mechanism and enhancing potato farmers’ ability to cope with market and natural risks; and improving the potato reserve system and potato storage facilities.

CRISPR-activation screen identified potassium channels for protection against mycotoxins through cell cycle progression and mitochondrial function.

Zearalenone (ZEA) exposure has carcinogenic effects on human and animal health by exhibiting intestinal, hepatic, and renal toxicity. At present, the underlying mechanisms on how ZEA induces apoptosis and damage to tissues still remain unclear. In this study, we aimed to identify genes that modulate the cellular response to ZEA using clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 screening, and further validate novel gene functions to elucidate molecular mechanisms underlying particular biological processes in vivo and in vitro. Two ZEA-resistant cell lines, designated Ov-KCNJ4 and Ov-KCNJ12, were yielded by CRISPR activation screening which had significant changes in ZEA resistance and growth rates. Results showed that ZEA could interact with the cell membrane proteins KCNJ4 and KCNJ12, inducing cell cycle arrest, disruption of DNA replication and base excision repair. Overexpression of KCNJ4 and KCNJ12 was involved in ZEA resistance by regulating cell cycle to neutralize toxicity, sustaining mitochondrial morphology and function via attenuating the damage from oxidative stress in the KCNJ4-mitoKATP pathway. In vivo experiments showed that AAV-KCNJ4 delivery significantly improved ZEA-induced renal impairment and increased antioxidative enzyme activity by improving mitochondrial function. Our findings suggest that increasing potassium channel levels may be a putative therapeutic target for mycotoxin-induced damage.

Trait interactions effects on tropical tree demography depend on the environmental context

Although functional traits are defined based on their impact on demographic parameters, trait-demography relationships are often reported as weak. These weak relationships might be due to disregarding trait interactions and environmental contexts, which should modulate species trait-demography relationships. We applied different models, including boosted regression tree (BRT) models, to investigate changes in the relationship between traits and demographic rates of tropical tree species in plots along an elevational gradient and among time intervals between censuses, analyzing the effect of a strong drought event. Based on a large dataset of 18,000 tree individuals from 133 common species, distributed among twelve 1-ha plots (habitats) in the Atlantic Forest (Brazil), we evaluated how trait interactions and the environmental context influence the demographic rates (growth, mortality, and recruitment). Functional traits, trait-trait, and trait-habitat interactions predicted demography with a good fit through either BRTs or linear mixed-models. Changes in growth rates were best related to size (diameter), and mortality rates to habitats, while changes in recruitment rates were best related to the specific leaf area. Moreover, the influence of traits differed among time intervals, and for demographic parameters, habitat affected growth and mortality by interacting with diameter. Here, we provide evidence that trait-demography relationships can be improved when considering the environmental context (space and time) and trait interactions to cope with the complexity of changes in the demography of tropical tree communities. Thus, to expand predictions of demography based on functional traits, we show that it is useful to fully incorporate the concept of multiple trait-fitness optima, resulting from trait interactions in different habitats and growth conditions.