The bioenergetics response of the coral Pocillopora damicornis to temperature changes during its reproduction stage.

Sexual reproduction of reef-building corals is vital for coral reef ecosystem recovery. Corals allocate limited energy to growth and reproduction, when being under environmental disturbance, which ultimately shapes the community population dynamics. In the present study, energetic and physiological parameters of both parental colonies and larvae of the coral Pocillopora damicornis were measured during their reproduction stage under four temperatures; 28 °C (low-temperature acclimation, LA), 29 °C (control temperature, CT), 31 °C (high-temperature acclimation, HA), and 32 °C (heat stress, HS). The results showed temperature changes altered the larvae release timing and fecundity in P. damicornis. Parental colonies exposed to the LA treatment exhibited reduced investment in reproduction and released fewer larvae, while retaining more energy for their development. However, each larva acquired higher energy and symbiont densities enabling survival through longer planktonic periods before settlement. In contrast, parental colonies exposed to the HA treatment had increased investment for reproduction and larvae output, while per larva gained less energy to mitigate the threat of higher temperature. Furthermore, the energy allocation processes restructured fatty acids concentration and composition in both parental colonies and larvae as indicated by shifts in membrane fluidity under adaptable temperature changes. Notably, parental colonies from the HS treatment expended more energy in response to heat stress, resulting in adverse effects, especially after larval release. Our study expands the current knowledge on the energy allocation strategies of P. damicornis and how it is impacted by temperature. Parental colonies employed different energy allocation strategies under distinct temperature regimes to optimize their development and offspring success, but under heat stress, both were compromised. Lipid metabolism is essential for the success of coral reproduction and further understanding their response to heat stress can improve intervention strategies for coral reef conservation in warmer future oceans.

The expression of AcIDI1 reveals diterpenoid alkaloids' allocation strategies in the roots of Aconitum carmichaelii Debx.

Isopentenyl diphosphate isomerase (IDI), a key enzyme in the biosynthetic pathway of diterpenoid alkaloids (DAs), plays an essential regulatory role in the synthesis and accumulation of DAs. In this study, the coding sequence (CDS) of AcIDI1 was isolated from the mother roots of Aconitum carmichaelii Debx. (GeneBank accession number OR915879). Bioinformatics analysis showed that the CDS of AcIDI1 was 894 bp, encoding a protein with 297 amino acids and the putative protein localized in the chloroplast. AcIDI1 exhibited significant homology with sequences encoding IDI in other species, and was most closely related to Aconitum vilmorinianum. Furthermore, the fusion protein has been successfully expressed in Escherichia coli (E. coli), providing a basis for future functional studies of AcIDI1. The expression pattern of AcIDI1 was analyzed by real-time quantitative PCR (qPCR), which demonstrates that AcIDI1 is a tissue-specific gene in the roots of A. carmichaelii and exhibits high expression in both daughter and mother roots. By comparing the expression levels of AcIDI1 in three tissues of the roots of A. carmichaelii at different growth stages, we propose that the mother roots (MRs) are the centers of resources allocation. The roots of A. carmichaelii continuously absorb the energy from external environment, while resources transfer behavior from MRs to both daughter roots (DRs) and axillary buds (ABs) occurs as the plant grows. This study establishes a foundation for applying the IDI gene to regulate the biosynthesis and accumulation of DAs in A. carmichaelii.

Joint Impacts of Meloidogyne incognita and Soil Nutrition on Solanum lycopersicum var. cerasiforme.

Strategies for plant nutrient resource allocation under Meloidogyne spp. infection and different soil nutrient conditions are not well established. In response, the objectives of this research are to determine if increased vegetative growth of Solanum lycopersicon var. cerasiforme (cherry tomato) under high nutrition enhances resistance to M. incognita and whether adaptive strategies for growth, reproduction, and nutrient uptake by cherry tomato infected with M. incognita alter nutrient availability. The study was conducted under greenhouse conditions using high, medium, and low soil nutrient regimes. The research results indicate that the total biomass of cherry tomato was less in the presence of M. incognita infection under all three nutrient conditions, compared with plants grown in the absence of this nematode. However, the increase in the root/shoot ratio indicates that cherry tomato allocated more resources to belowground organs. Under the combined impacts of M. incognita infection and low or medium soil nutrition, the nitrogen content in root system tissues and the phosphorus content in shoot system tissues were increased to meet the nutrient requirements of galled root tissue and plant fruit production. It is suggested that plants increase the allocation of reproductive resources to fruits by improving phosphorus transportation to the aboveground reproductive tissues under low and medium nutrient conditions. Overall, the study highlights a significant impact of soil nutrient levels on the growth and resource allocation associated with M. incognita-infected cherry tomato. In response, soil nutrient management is another practice for reducing the impacts of plant-parasitic nematodes on crop production.

Source Contributions to PM2.5-Related Mortality and Costs: Evidence for Emission Allocation and Compensation Strategies in China.

The emissions from various pollution sources were not proportional to their contributions to ambient PM2.5 concentrations and associated health burdens. That means even with the same total abatement targets, different abatement allocation strategies across emission sources can have distinct health benefits. Insufficient knowledge of various sources' contributions to health burdens in China, the country suffering substantial PM2.5-related deaths, hindered the government from seeking optimized abatement allocation strategies. In this context, we separated the contributions of 155 emission sources (31 provinces × 5 sectors) to PM2.5-related mortality across China in 2017 by coupling the Comprehensive Air Quality Model with Extensions (CAMx), Weather Research and Forecasting model (WRF), and health impact assessment model. We further identified the priority-control emission sources and quantified interprovincial ecological compensation volumes to alleviate inequality induced by emission allocation strategies. Results showed that PM2.5 pollution caused 899,443 excess deaths and around 127 billion USD costs in 2017. Approximately half of the deaths and costs were attributable to emissions from sources outside the boundary of the regions where the deaths occurred. Twenty-five out of 155 emission sources that contributed to the top 60% mortality burdens and had high marginal abatement efficiencies in China shall be the priority-control emission sources. A 1 µg/m3 decrease of PM2.5 concentration in regions where these key emission sources occur shall be compensated by 76-153 million USD in their receptor regions. Our study sheds light on the sources' contributions to mortality burdens and costs and provides scientific evidence for optimizing the emission allocation and compensation strategies in China. It also has wide implications for other countries suffering similar problems.

Nutrient allocation strategies of four conifers from semiarid to extremely arid environments.

Although the contents of limiting elements in plants, such as nitrogen (N) and phosphorus (P), have been widely studied from subtropical to humid-temperate zones, the strategies used by coniferous species to allocation N and P in arid and semiarid forests remain unclear. In this study, samples of 545 leaves, 194 twigs, and 78 fine roots were collected from four coniferous species (Pinus tabuliformis, Picea wilsonii, Juniperus przewalskii, and Picea crassifolia) of three genera (Pinus, Picea, and Juniperus) in the northeastern Tibetan Plateau, and the contents of C, N, and P were analyzed. Two key parameters, namely the allometric exponent and coefficient of variation, were calculated to illustrate the relative investment of plants to N and P uptake and plasticity (variation of N and P), respectively. The contents of N and P and the N:P ratios were the highest in leaves, but their plasticity was the lowest. This confirmed the hypothesis that the leaves of coniferous species have a high content of limiting nutrients and homeostasis. At the regional level, the allometric exponent of N and P in leaves was 0.68, 0.74 in twigs, and 0.78 in fine roots, which is consistent with the results on a global scale. Thus, this invariant allometric relationship suggests the existence of an important mechanism that constrains the allocation of plant nutrients across broad environmental gradients. However, the allocation strategies for N and P shifted with the species, climate, and soil nutrients. Namely: their preferred nutrient uptake was P when the trees had a better nutritional status (semiarid environments, mean annual precipitations (MAP) > 300 mm), but the investment of N was strengthened when the habitat conditions become more severe (extremely arid environments, MAP <100 mm). Thus, our results can provide a novel perspective to understand the strategies of plant nutrient uptake in arid and semiarid forests.

Comparison of health-oriented cross-regional allocation strategies for the COVID-19 vaccine: a mathematical modelling study.

BACKGROUND: Controlling the epidemic spread and establishing the immune barrier in a short time through accurate vaccine demand prediction and optimised vaccine allocation strategy are still urgent problems to be solved under the condition of frequent virus mutations. METHODS: A cross-regional Susceptible-Exposed-Infected-Removed dynamic model was used for scenario simulation to systematically elaborate and compare the effects of different cross-regional vaccine allocation strategies on the future development of the epidemic in regions with different population sizes, prevention and control capabilities, and initial risk levels. Furthermore, the trajectory of the cross-regional vaccine allocation strategy, calculated using a particle swarm optimisation algorithm, was compared with the trajectories of other strategies. RESULTS: By visualising the final effect of the particle swarm optimisation vaccine allocation strategy, this study revealed the important role of prevention and control (including the level of social distancing control, the speed of tracking and isolating exposed and infected individuals, and the initial frequency of mask-wearing) in determining the allocation of vaccine resources. Most importantly, it supported the idea of prioritising control in regions with a large population and low initial risk level, which broke the general view that high initial risk needs to be given priority and proposed that outbreak risk should be firstly considered instead. CONCLUSIONS: This is the first study to use a particle swarm optimisation algorithm to study the cross-regional allocation of COVID-19 vaccines. These data provide a theoretical basis for countries and regions to develop more targeted and sustainable vaccination strategies.KEY MESSAGEThe innovative combination of particle swarm optimisation and cross-regional SEIR model to simulate the pandemic trajectory and predict the vaccine demand helped to speed up and stabilise the construction of the immune barrier, especially faced with new virus mutations.We proposed that priority should be given to regions where it is possible to prevent more infections rather than regions where it is at high initial risk, thus regional outbreak risk should be considered when making vaccine allocation decisions.An optimal health-oriented strategy for vaccine allocation in the COVID-19 pandemic is determined considering both pharmaceutical and non-pharmaceutical policy interventions, including speed of isolation, degree of social distancing control, and frequency of mask-wearing.

Providing laypeople with results from dynamic infectious disease modelling studies affects their allocation preference for scarce medical resources-a factorial experiment.

BACKGROUND: Allocation of scarce medical resources can be based on different principles. It has not yet been investigated which allocation schemes are preferred by medical laypeople in a particular situation of medical scarcity like an emerging infectious disease and how the choices are affected by providing information about expected population-level effects of the allocation scheme based on modelling studies. We investigated the potential benefit of strategic communication of infectious disease modelling results. METHODS: In a two-way factorial experiment (n = 878 participants), we investigated if prognosis of the disease or information about expected effects on mortality at population-level (based on dynamic infectious disease modelling studies) influenced the choice of preferred allocation schemes for prevention and treatment of an unspecified sexually transmitted infection. A qualitative analysis of the reasons for choosing specific allocation schemes supplements our results. RESULTS: Presence of the factor "information about the population-level effects of the allocation scheme" substantially increased the probability of choosing a resource allocation system that minimized overall harm among the population, while prognosis did not affect allocation choices. The main reasons for choosing an allocation scheme differed among schemes, but did not differ among those who received additional model-based information on expected population-level effects and those who did not. CONCLUSIONS: Providing information on the expected population-level effects from dynamic infectious disease modelling studies resulted in a substantially different choice of allocation schemes. This finding supports the importance of incorporating model-based information in decision-making processes and communication strategies.

Assessing Hospital Adaptive Resource Allocation Strategies in Responding to Mass Casualty Incidents.

OBJECTIVES: Hospitals are expected to operate at a high-performance level even under exceptional conditions of peak demand and resource disruptions. This understanding is not mature yet, and there are wide areas of possible improvement. In particular, the fast mobilization and reconfiguration of resources frequently result into the severe disruption of elective activities, worsening the quality of care. More resilient resource allocation strategies, ie, which adapt to the dynamics of the prevailing circumstance, are needed to maximize the effectiveness of health-care delivery. In this study, a simulation approach was adopted to assess and compare different hospital's adaptive resource allocation strategies in responding to a mass casualty incident (MCI). METHODS: A specific set of performance metrics was developed to take into consideration multiple objectives and priorities and holistically assess the effectiveness of health-care delivery when coping with an MCI event. Discrete event simulation (DES) and system dynamics (SD) were used to model the key hospital processes and the MCI plan. RESULTS: In the daytime scenario, during the recovery phase of the emergency, a gradual disengagement of resources from the emergency department (ED) to restart ordinary activities in operating rooms and wards, returned the best performance. In the night scenario, the absorption capacity of the ED was evaluated by identifying the current bottleneck and assessment of the benefit of different resource mobilization strategies. CONCLUSIONS: The present study offers a robust approach, effective strategies, and new insights to design more resilient plans to cope with MCIs. Future research is needed to widen the scope of the analysis and take into consideration additional resilience capacities, such as operational coordination mechanisms, among multiple hospitals in the same geographic area.

Dynamics of Soil Microbial N-Cycling Strategies in Response to Cadmium Stress.

Globally increasing trace metal contamination of soils requires a better mechanistic understanding of metal-stress impacts on microbially mediated nutrient cycling. Herein, a 5-month laboratory experiment was employed to assess the effects of cadmium (Cd) on soil microbial N-cycling processes and associated functional gene abundance, with and without urea amendment. In non-N-amended soils, Cd progressively stimulated microbial populations for N acquisition from initial dissolved organic N (DON) to later recalcitrant organic N. The acceleration of N catabolism was synchronously coupled with C catabolism resulting in increased CO2/N2O fluxes and adenosine triphosphate (ATP) contents. The abundance of microbes deemed inefficient in N catabolism was gradually repressed after an initial stimulation period. We posit that enhanced exergonic N processes diminished the need for endergonic activities as a survival strategy for N communities experiencing metal stress. With urea amendment, Cd exhibited an initial stimulation effect on soil nitrification and a later a promotion effect on mineralization, along with an increase in the associated microbial populations. In N-amended soils, Cd accelerated N/C transformation processes, but decreased N2O and CO2 fluxes by 19 and 14%, respectively. This implies that under eutrophic conditions, Cd synchronously altered microbial C/N metabolism from a dominance of catabolic to anabolic processes. These results infer a nutrient-based adjustment of microbial N-cycling strategies to enhance their metal resistance.

Modeling asset allocations and a new portfolio performance score.

We discuss and extend a powerful, geometric framework to represent the set of portfolios, which identifies the space of asset allocations with the points lying in a convex polytope. Based on this viewpoint, we survey certain state-of-the-art tools from geometric and statistical computing to handle important and difficult problems in digital finance. Although our tools are quite general, in this paper, we focus on two specific questions. The first concerns crisis detection, which is of prime interest for the public in general and for policy makers in particular because of the significant impact that crises have on the economy. Certain features in stock markets lead to this type of anomaly detection: Given the assets' returns, we describe the relationship between portfolios' return and volatility by means of a copula, without making any assumption on investors' strategies. We examine a recent method relying on copulae to construct an appropriate indicator that allows us to automate crisis detection. On real data the indicator detects all past crashes in the cryptocurrency market and from the DJ600-Europe index, from 1990 to 2008, the indicator identifies correctly 4 crises and issues one false positive for which we offer an explanation. Our second contribution is to introduce an original computational framework to model asset allocation strategies, which is of independent interest for digital finance and its applications. Our approach addresses the crucial question of evaluating portfolio management, and is relevant the individual managers as well as financial institutions. To evaluate portfolio performance, we provide a new portfolio score, based on the aforementioned framework and concepts. In particular, it relies on statistical properties of portfolios, and we show how they can be computed efficiently.

Global patterns of leaf construction traits and their covariation along climate and soil environmental gradients.

Leaf functional traits and their covariation underlie plant ecological adaptations along environmental gradients, but there is limited information on the global covariation patterns of key leaf construction traits. To explore how leaf construction traits co-vary across diverse climate and soil environmental conditions, we compiled a global dataset including cell wall mass per unit leaf mass (CWmass ), leaf carbon (C) and calcium (Ca) concentrations, and specific leaf area (SLA) for 2348 angiosperm species from 340 sites world-wide. Our results demonstrated negative correlations between leaf C and Ca concentrations and between leaf C and SLA across diverse nongraminoid angiosperms. Leaf C concentration increased with increasing mean annual temperature (MAT) and mean annual precipitation (MAP) and with decreasing soil pH and calcium carbonate (CaCO3 ) concentration, whereas leaf Ca concentration and SLA exhibited the opposite responses to these environmental variables. The covariations of leaf Ca-C and of leaf SLA-C were stronger in habitats with lower MAT and MAP, and/or higher soil CaCO3 content. This global-scale analysis demonstrates that the leaf C and Ca concentrations and SLA together govern the C and biomass investment strategies in leaves of nongraminoids. We conclude that environmental conditions strongly shape leaf construction traits and their covariation patterns.

Assessing Hospital Adaptive Resource Allocation Strategies in Responding to Mass Casualty Incidents.

BACKGROUND: Hospitals are expected to operate at a high performance level even under exceptional conditions of peak demand and resource disruptions. This understanding is not mature yet and there are wide areas of possible improvement. In particular, the fast mobilization and reconfiguration of resources frequently result into the severe disruption of elective activities, worsening the quality of care. This becomes particularly evident during the on-going coronavirus disease 2019 (COVID-19) pandemic. More resilient resource allocation strategies, that is, which adapt to the dynamics of the prevailing circumstance, are needed to maximize the effectiveness of health-care delivery. In this study, a simulation approach was adopted to assess and compare different hospital's adaptive resource allocation strategies in responding to a sudden onset disaster mass casualty incident (MCI). METHODS: A specific set of performance metrics was developed to take into consideration multiple objectives and priorities and holistically assess the effectiveness of health-care delivery when coping with an MCI event. Discrete event simulation (DES) and system dynamics (SD) were used to model the key hospital processes and the MCI plan. RESULTS: In the daytime scenario, during the recovery phase of the disaster, a gradual disengagement of resources from the emergency department (ED) to restart ordinary activities in operating rooms and wards returned the best performance. In the night scenario, the absorption capacity of the ED was evaluated by identifying the current bottleneck and assessment of the benefit of different resource mobilization strategies. CONCLUSIONS: The present study offers a robust approach, effective strategies and new insights to design more resilient plans to cope with MCIs. It becomes particularly relevant when considering the risk of indirect damage of emergencies, where all the available resources are shifted from the care of the ordinary to the "disaster" patients, like during the on-going COVID-19 pandemic. Future research is needed to widen the scope of the analysis and take into consideration additional resilience capacities such as operational coordination mechanisms among multiple hospitals in the same geographic area.

Strong impact of management regimes on rhizome biomass across Central European temperate grasslands.

Grassland ecosystems account for approximately 40% of terrestrial biomes globally. These communities are characterized by a large allocation to belowground biomass, often exceeding its aboveground counterpart. However, this biomass investment cannot be entirely attributed to the acquisitive function of roots. Grassland plants also allocate to non-acquisitive, stem-derived, belowground organs, such as rhizomes. These organs are responsible for the key plant functions of space occupancy, resprouting after damage, and seasonal rest. However, biomass investment to rhizomes has rarely been studied. Here we gathered community-level aboveground and rhizome biomass data for 52 temperate grasslands in Czech Republic (Central Europe), differing in management intensity. We found that rhizome biomass scaled linearly with aboveground biomass, and more intensive management disproportionally (negatively) affected rhizome biomass. This finding may have important implications for the persistence of temperate grassland plants and their provision of ecosystem services (e.g., soil carbon sequestration, soil stabilization) in relation to changing environments.

Information-Theoretic Radar Waveform Design under the SINR Constraint.

This study investigates the information-theoretic waveform design problem to improve radar performance in the presence of signal-dependent clutter environments. The goal was to study the waveform energy allocation strategies and provide guidance for radar waveform design through the trade-off relationship between the information theory criterion and the signal-to-interference-plus-noise ratio (SINR) criterion. To this end, a model of the constraint relationship among the mutual information (MI), the Kullback-Leibler divergence (KLD), and the SINR is established in the frequency domain. The effects of the SINR value range on maximizing the MI and KLD under the energy constraint are derived. Under the constraints of energy and the SINR, the optimal radar waveform method based on maximizing the MI is proposed for radar estimation, with another method based on maximizing the KLD proposed for radar detection. The maximum MI value range is bounded by SINR and the maximum KLD value range is between 0 and the Jenson-Shannon divergence (J-divergence) value. Simulation results show that under the SINR constraint, the MI-based optimal signal waveform can make full use of the transmitted energy to target information extraction and put the signal energy in the frequency bin where the target spectrum is larger than the clutter spectrum. The KLD-based optimal signal waveform can therefore make full use of the transmitted energy to detect the target and put the signal energy in the frequency bin with the maximum target spectrum.

Carbon, Nitrogen, and Phosphorus Allocation Strategy Among Organs in Submerged Macrophytes Is Altered by Eutrophication.

The allocation of limiting elements among plant organs is an important aspect of the adaptation of plants to their ambient environment. Although eutrophication can extremely alter light and nutrient availability, little is known about nutrient partitioning among organs of submerged macrophytes in response to eutrophication. Here, we analyzed the stoichiometric scaling of carbon (C), nitrogen (N), and phosphorus (P) concentrations among organs (leaf, stem, and root) of 327 individuals of seven common submerged macrophytes (three growth forms), sampled from 26 Yangtze plain lakes whose nutrient levels differed. Scaling exponents of stem nutrients to leaf (or root) nutrients varied among the growth forms. With increasing water total N (WTN) concentration, the scaling exponents of stem C to leaf (or root) C increased from <1 to >1, however, those of stem P to root P showed the opposite trend. These results indicated that, as plant nutrient content increased, plants growing in low WTN concentration accumulated leaf C (or stem P) at a faster rate, whereas those in high WTN concentration showed a faster increase in their stem C (or root P). Additionally, the scaling exponents of stem N to leaf (or root) N and stem P to leaf P were consistently large than 1, but decreased with a greater WTN concentration. This suggested that plants invested more N and P into stem than leaf tissues, with a higher investment of N in stem than root tissues, but eutrophication would decrease the allocation of N and P to stem. Such shifts in plant nutrient allocation strategies from low to high WTN concentration may be attributed to changed light and nutrient availability. In summary, eutrophication would alter nutrient allocation strategies of submerged macrophytes, which may influence their community structures by enhancing the competitive ability of some species in the process of eutrophication.

Variation in ecophysiological traits might contribute to ecogeographic isolation and divergence between parapatric ecotypes of Mimulus aurantiacus.

Many forms of reproductive isolation contribute to speciation, and early-acting barriers may be especially important, because they have the first opportunity to limit gene flow. Ecogeographic isolation occurs when intrinsic traits of taxa contribute to disjunct geographic distributions, reducing the frequency of intertaxon mating. Characterizing this form of isolation requires knowledge of both the geographic arrangement of suitable habitats in nature and the identification of phenotypes involved in shaping geographic distributions. In Mimulus aurantiacus, red- and yellow-flowered ecotypes are incompletely isolated by divergent selection exerted by different pollinators. However, these emerging taxa are largely isolated spatially, with a hybrid zone occurring along a narrow region of contact. In order to assess whether responses to abiotic conditions contribute to the parapatric distribution of ecotypes, we measured a series of ecophysiological traits from populations along a transect, including drought sensitivity, leaf area and the concentrations of vegetative flavonoids. In contrast to the abrupt transitions in floral phenotypes, we found that ecophysiological traits exhibited a continuous geographic transition that largely mirrors variation in climatological variables. These traits may impede gene flow across a continuous environmental gradient, but they would be unlikely to result in ecotypic divergence alone. Nevertheless, we found a genetic correlation between vegetative and floral traits, providing a potential link between the two forms of isolation. Although neither barrier appears sufficient to cause divergence on its own, the combined impacts of local adaptation to abiotic conditions and regional adaptation to pollinators may interact to drive discontinuous variation in the face of gene flow in this system.

Effects of soil nitrogen on diploid advantage in fireweed, Chamerion angustifolium (Onagraceae).

In many ecosystems, plant growth and reproduction are nitrogen limited. Current and predicted increases of global reactive nitrogen could alter the ecological and evolutionary trajectories of plant populations. Nitrogen is a major component of nucleic acids and cell structures, and it has been predicted that organisms with larger genomes should require more nitrogen for growth and reproduction and be more negatively affected by nitrogen scarcities than organisms with smaller genomes. In a greenhouse experiment, we tested this hypothesis by examining whether the amount of soil nitrogen supplied differentially influenced the performance (fitness, growth, and resource allocation strategies) of diploid and autotetraploid fireweed (Chamerion angustifolium). We found that soil nitrogen levels differentially impacted cytotype performance, and in general, diploids were favored under low nitrogen conditions, but this diploid advantage disappeared under nitrogen enrichment. Specifically, when nitrogen was scarce, diploids produced more seeds and allocated more biomass toward seed production relative to investment in plant biomass or total plant nitrogen than did tetraploids. As nitrogen supplied increased, such discrepancies between cytotypes disappeared. We also found that cytotype resource allocation strategies were differentially dependent on soil nitrogen, and that whereas diploids adopted resource allocation strategies that favored current season reproduction when nitrogen was limiting and future reproduction when nitrogen was more plentiful, tetraploids adopted resource allocation strategies that favored current season reproduction under nitrogen enrichment. Together these results suggest nitrogen enrichment could differentially affect cytotype performance, which could have implications for cytotypes' ecological and evolutionary dynamics under a globally changing climate.

Enhanced shoot investment makes invasive plants exhibit growth advantages in high nitrogen conditions / O investimento de tiro aumentado faz plantas invasivas exposição de vantagens de crescimento em altas condições de nitrógeno

Abstract Resource amendments commonly promote plant invasions, raising concerns over the potential consequences of nitrogen (N) deposition; however, it is unclear whether invaders will benefit from N deposition more than natives. Growth is among the most fundamental inherent traits of plants and thus good invaders may have superior growth advantages in response to resource amendments. We compared the growth and allocation between invasive and native plants in different N regimes including controls (ambient N concentrations). We found that invasive plants always grew much larger than native plants in varying N conditions, regardless of growth- or phylogeny-based analyses, and that the former allocated more biomass to shoots than the latter. Although N addition enhanced the growth of invasive plants, this enhancement did not increase with increasing N addition. Across invasive and native species, changes in shoot biomass allocation were positively correlated with changes in whole-plant biomass; and the slope of this relationship was greater in invasive plants than native plants. These findings suggest that enhanced shoot investment makes invasive plants retain a growth advantage in high N conditions relative to natives, and also highlight that future N deposition may increase the risks of plant invasions.

Resumo As alterações de recursos geralmente promovem invasões de plantas, suscitando preocupações quanto às conseqüências potenciais da deposição de nitrogênio (N); No entanto, não está claro se os invasores se beneficiarão da deposição de N mais do que com os nativos. O crescimento é um dos traços inerentes mais fundamentais das plantas e, portanto, os bons invasores podem ter vantagens de crescimento superiores em resposta a alterações de recursos. Comparamos o crescimento e a alocação entre plantas invasivas e nativas em diferentes regimes de N, incluindo controles (concentrações ambientais de N). Descobrimos que as plantas invasivas sempre cresceram muito mais do que as plantas nativas em diferentes condições de N, independentemente das análises baseadas em crescimento ou filogenia, e que o primeiro atribuiu mais biomassa aos rebentos do que o segundo. Embora N aumentou o crescimento de plantas invasivas, esse aumento não aumentou com o aumento da adição de N. Através das espécies invasivas e nativas, as mudanças na alocação da biomassa do extrato foram correlacionadas positivamente com as mudanças na biomassa da planta inteira; e a inclinação desse relacionamento foi maior em plantas invasivas do que plantas nativas. Essas descobertas sugerem que o aumento do investimento em lançamentos faz com que as plantas invasivas mantenham uma vantagem de crescimento em altas condições de N em relação aos nativos, e também destacar que a futura deposição de N pode aumentar os riscos de invasões de plantas.

Digital Stratigraphy: Contextual Analysis of File System Traces in Forensic Science.

This work introduces novel methods for conducting forensic analysis of file allocation traces, collectively called digital stratigraphy. These in-depth forensic analysis methods can provide insight into the origin, composition, distribution, and time frame of strata within storage media. Using case examples and empirical studies, this paper illuminates the successes, challenges, and limitations of digital stratigraphy. This study also shows how understanding file allocation methods can provide insight into concealment activities and how real-world computer usage can complicate digital stratigraphy. Furthermore, this work explains how forensic analysts have misinterpreted traces of normal file system behavior as indications of concealment activities. This work raises awareness of the value of taking the overall context into account when analyzing file system traces. This work calls for further research in this area and for forensic tools to provide necessary information for such contextual analysis, such as highlighting mass deletion, mass copying, and potential backdating.

Biomass and nutrient allocation strategies in a desert ecosystem in the Hexi Corridor, northwest China.

The allocation of biomass and nutrients in plants is a crucial factor in understanding the process of plant structures and dynamics to different environmental conditions. In this study, we present a comprehensive scaling analysis of data from a desert ecosystem to determine biomass and nutrient (carbon (C), nitrogen (N), and phosphorus (P)) allocation strategies of desert plants from 40 sites in the Hexi Corridor. We found that the biomass and levels of C, N, and P storage were higher in shoots than in roots. Roots biomass and nutrient storage were concentrated at a soil depth of 0-30 cm. Scaling relationships of biomass, C storage, and P storage between shoots and roots were isometric, but that of N storage was allometric. Results of a redundancy analysis (RDA) showed that soil nutrient densities were the primary factors influencing biomass and nutrient allocation, accounting for 94.5% of the explained proportion. However, mean annual precipitation was the primary factor influencing the roots biomass/shoots biomass (R/S) ratio. Furthermore, Pearson's correlations and regression analyses demonstrated that although the biomass and nutrients that associated with functional traits primarily depended on soil conditions, mean annual precipitation and mean annual temperature had greater effects on roots biomass and nutrient storage.