Relative Allocation Of Resources Research Articles

The Impact of Differences in Surveillance Definitions of Hospital Acquired Urinary Tract Infections (HAUTI).

Hospital-acquired urinary tract infections (HAUTI) are common and most cases are related to catheters (CAUTI). HAUTI and CAUTI surveillance is mandatory in many countries as a measure to reduce the incidence of infections and appropriately direct the allocation of preventable resources. The surveillance criteria issued by the Israeli Ministry of Health (IMOH), differ somewhat from that of the U.S. Centers for Disease Control and Prevention (CDC). Our study aims were to query and quantify the impact of these differences. In a retrospective cohort study conducted at Shamir Medical Center, for calendar year 2017, the surveillance criteria of both IMOH and CDC were applied on 644 patient-unique adults with “positive” urine cultures (per similar definitions). The incidence of HAUTI per IMOH was significantly higher compared to CDC (1.24/1000 vs. 1.02/1000 patient-days, p = 0.02), with no impact on hospitalization’s outcomes. The agreement rate between methods was high for CAUTI (92%), but much lower for all HAUTI (83%). The major error rate, i.e., patients diagnosed with HAUTI per IMOH but had no UTI per CDC, was 31%. To conclude, in order for surveillance to reflect the relative situation and direct allocation of preventable resources based on scientific literature, the process should be uniform worldwide.

BLOCKCHAIN FORKS: A FORMAL CLASSIFICATION FRAMEWORK AND PERSISTENCY ANALYSIS

Blockchain forks can have severe economic implications, sow uncertainty and undermine trust. In this paper, we introduce a formal framework to study the emergence, persistency and economic consequences of blockchain forks. We argue that blockchain forks can be process- or protocol-based and emerge unintentionally or deliberately. We then proceed with a sub-classification of protocol-based forks and study the circumstances under which a chain split may become permanent. It can be shown that the persistency of a fork depends on the nature of the change to the consensus rules and on the relative allocation of the consensus-relevant resources. Lastly, we discuss business implications as well as potential consequences for policy makers and practitioners.

Diversificación productiva y cambio estructural en economías cerradas y abiertas

Productive diversification has been the main determinant of structural change of the economies. This hypothesis is analysed for nine countries under a relatively closed trade regime, and for nine Latin American countries under a relatively open trade regime with the United States. The equations of structural change that are tested are derived from a multisector dynamic general equilibrium model. The negative impact of productive diversification on the relative allocation of resources to the primary sector cannot be rejected for closed economies: greater diversification increases the relative productivity of manufacturing activities. The impact of a country’s comparative advantages on the allocation of resources to agriculture cannot be rejected: the relative agricultural productivity has a positive impact; the relative capital endowment has a negative impact; and the real exchange rate has a positive impact. In the last case, it is argued that low diversification induces a deterioration in the terms of trade, which favours specialization in primary activities.

Three-Dimensional Time-Lapse Analysis Reveals Multiscale Relationships in Maize Root Systems with Contrasting Architectures.

Understanding how an organism's phenotypic traits are conditioned by genetic and environmental variation is a central goal of biology. Root systems are one of the most important but poorly understood aspects of plants, largely due to the three-dimensional (3D), dynamic, and multiscale phenotyping challenge they pose. A critical gap in our knowledge is how root systems build in complexity from a single primary root to a network of thousands of roots that collectively compete for ephemeral, heterogeneous soil resources. We used time-lapse 3D imaging and mathematical modeling to assess root system architectures (RSAs) of two maize (Zea mays) inbred genotypes and their hybrid as they grew in complexity from a few to many roots. Genetically driven differences in root branching zone size and lateral branching densities along a single root, combined with differences in peak growth rate and the relative allocation of carbon resources to new versus existing roots, manifest as sharply distinct global RSAs over time. The 3D imaging of mature field-grown root crowns showed that several genetic differences in seedling architectures could persist throughout development and across environments. This approach connects individual and system-wide scales of root growth dynamics, which could eventually be used to predict genetic variation for complex RSAs and their functions.

Fight or flight? Potential tradeoffs between drought defense and reproduction in conifers.

Plants frequently exhibit tradeoffs between reproduction and growth when resources are limited, and often change these allocation patterns in response to stress. Shorter-lived plants such as annuals tend to allocate relatively more resources toward reproduction when stressed, while longer-lived plants tend to invest more heavily in survival and stress defense. However, severe stress may affect the fitness implications of allocating relatively more resources to reproduction versus stress defense. Increased drought intensity and duration have led to widespread mortality events in coniferous forests. In this review, we ask how potential tradeoffs between reproduction and survival influence the likelihood of drought-induced mortality and species persistence. We propose that trees may exhibit what we call 'fight or flight' behaviors under stress. 'Fight' behaviors involve greater resource allocation toward survival (e.g., growth, drought-resistant xylem and pest defense). 'Flight' consists of higher relative allocation of resources to reproduction, potentially increasing both offspring production and mortality risk for the adult. We hypothesize that flight behaviors increase as drought stress escalates the likelihood of mortality in a given location.

Differential tolerance of native and invasive tree seedlings from arid African deserts to drought and shade

Efforts to understand why some species become successful invaders and why some habitats are more at risk from invasive species is an important research focus in invasion ecology. With current global climate change, evaluation of the effects of shade and drought on cohabiting native and invasive species from extreme ecosystems is especially important. Acacia tortilis subsp. raddiana is a tree taxon native to arid African deserts. Prosopis glandulosa, native to the southwestern United States and Mexico, is invading African arid and semiarid regions that are habitat for A. t. subsp. raddiana. The aim of this study was to evaluate and compare the tolerance and responses of the seedlings of these two tree species to shade, water stress and their interactions. We measured and recorded growth rates and morphological, biochemical and physiological plant traits under two radiation and two water treatments in greenhouse conditions. Radiation intensity was a stronger driver of the performance of both species than water availability. Beyond the independent effects of shade and drought, the interactions of these factors yielded synergistic effects on seedlings of both tree species, affecting key plant traits. The seedlings of A. t. subsp. raddiana were able to implement important shifts in key functional traits in response to altering abiotic stress conditions, behaving as a stress-tolerant species that is well-adapted to the habitat it occupies in hot arid African deserts. In contrast, the fast-growing seedlings of P. glandulosa were stress-avoiding. The alien P. glandulosa seedlings were highly sensitive to water and shade stress. Moreover, they were particularly sensitive to drought in shade conditions. However, although alien P. glandulosa seedlings were exposed to high stress levels, they were able to avoid permanent damage to their photosynthetic apparatus by mechanisms such as increasing energy dissipation by heat emission and by adjusting the relative allocation of resources to above- and below-ground structures. Our results are useful for conservation planning and restoration of invaded hyperarid ecosystems.

The Effect of Ad Skepticism and Celebrity Preference on Brand Attitude Change in Celebrity‐Endorsed Advertising

AbstractThe use of a celebrity endorser who is well recognized and favorably evaluated by the target viewers is a common strategy used by advertisers to increase the persuasiveness of an advertisement. Yet, at the same time, being skeptical of the claim being made by the celebrity endorser is the typical response of the viewers to such persuasion attempts. The present research examines how these effects potentially counterbalance each other as viewers evaluate the advertised brand in a low‐involvement setting. The results show that the degree of ad skepticism and the relative allocation of attentional resources to celebrity and brand elements in advertisements determine how preference for a celebrity endorser is transferred to the advertised brand. The findings provide a more complete understanding of the psychological mechanisms by which celebrity preference influences brand attitude change than has previously been available. They indicate that ad skepticism may be the missing link in understanding the effectiveness of celebrity‐endorsed advertising.

Spatial variation in reproductive effort of a southern Australian seagrass

In marine environments characterised by habitat-forming plants, the relative allocation of resources into vegetative growth and flowering is an important indicator of plant condition and hence ecosystem health. In addition, the production and abundance of seeds can give clues to local resilience. Flowering density, seed bank, biomass and epiphyte levels were recorded for the temperate seagrass Zostera nigricaulis in Port Phillip Bay, south east Australia at 14 sites chosen to represent several regions with different physicochemical conditions. Strong regional differences were found within the large bay. Spathe and seed density were very low in the north of the bay (3 sites), low in the centre of the bay (2 sites) intermediate in the Outer Geelong Arm (2 sites), high in Swan Bay (2 sites) and very high in the Inner Geelong Arm (3 sites). In the south (2 sites) seed density was low and spathe density was high. These regional patterns were largely consistent for the 5 sites sampled over the three year period. Timing of flowering was consistent across sites, occurring from August until December with peak production in October, except during the third year of monitoring when overall densities were lower and peaked in November. Seagrass biomass, epiphyte load, canopy height and stem density showed few consistent spatial and temporal patterns. Variation in spathe and seed density and morphology across Port Phillip Bay reflects varying environmental conditions and suggests that northern sites may be restricted in their ability to recover from disturbance through sexual reproduction. In contrast, sites in the west and south of the bay have greater potential to recover from disturbances due to a larger seed bank and these sites could act as source populations for sites where seed production is low.

Conducting research that is both ethical and responsive to the health needs of a developing country

There is no substantial difference in conducting research that is both ethical and responsive to the health needs in developing and developed nations. Differences are in financial constraints, technological expertise in identification and addressing needs, and in the perception of equal partnership of all stakeholders. There will be differences in emphasis of research but this is slowly blurred due to globalisation. Public health emergencies in developing countries need timely and effective global collaborative research to implement control strategies. Research needs should be based on predictive models with learning from past emergencies, technological advances, strategic critical appraisal of local and global health information, and dialogue with all stakeholders. Adequate funding will be challenging and resources from national, international and aid foundations will be needed. Issues associated with such funding include deployment of international rapid response teams, collaborating researchers, transfer of technology, and intellectual property ownership. While all types of research ranging from basic, applied, clinical studies, meta-analysis, and translational research are relevant, the relative importance and specific allocation of resources to these may differ. Is the choice related to responsiveness or based on researchers' perception of their contributions to evidence-based practice and research? Ethical issues relating to vulnerable groups, risk distribution, quality issues, research integrity and oversight are just as important. Internationally funded research including clinical trials must be sensitive to such issues to avoid allegations of exploitation. Thus the potential of utilisation and buy-in of research findings and recommendations must be considered.

Scaling of antler size in reindeer (Rangifer tarandus): sexual dimorphism and variability in resource allocation

Male cervids face trade-offs in allocating resources to body mass (linked to survival) and antlers (linked to reproductive success). Reindeer (Rangifer tarandus) are unique among cervids because females also possess antlers, providing an opportunity to investigate sex- and age-specific patterns of resource allocation to body mass and antlers. Using long-term (1996–2011) data on 560 reindeer, we examined how body mass and antler length varied with age and sex, and the relative allocation of resources toward antlers using scaling analysis. Body mass and antler length increased through age 5 years in males but plateaued in females at age 3 years, with males 59% greater in body mass and 146% longer in antler length by age 5 years. All age and sex categories, except yearling males and mature females, had a positive scaling (a scaling exponent greater than isometry) of antlers with body mass, with the highest relative allocation of resources toward antlers in female calves. Relative allocation toward antlers tended to increase with age in males but decrease with age in females. The observed patterns in antler and body growth are likely a reflection of sex-specific life-history strategies of reindeer whereby females have offspring yearly from puberty and males have an increased number of offspring as they mature.

Food and Heat Stress in the California Mussel: Evidence for an Energetic Trade-off Between Survival and Growth

In response to thermal stress, many rocky shore organisms exhibit characteristic physiological changes associated with increased tolerance to subsequent high temperatures. Although presumably adaptive, activation of the heat-shock response requires a significant energetic investment and therefore may impose a trade-off between survival and other life-history traits. We investigated the effects of chronic heat stress and variation in food availability on the relative allocation of resources to competing demographic parameters in the California mussel, Mytilus californianus. Our data support the idea that acclimatory responses to temperature stress can drive trade-offs among traits, as predicted by theory. Chronic heat stress invoked a cost to individuals, expressed as a reduction in shell growth or size-specific tissue mass in the field and laboratory, respectively. At the same time, prior thermal conditioning resulted in higher proportional survival after acute exposure to more extreme temperatures. Overall, mussels receiving less food exhibited poor condition and survival relative to individuals fed more, suggesting that individuals with limited access to resources are at greater risk because they are less able to mitigate potential costs of thermal stress through physiological mechanisms. Accurately forecasting the effects of climate change in rocky intertidal ecosystems will therefore require understanding not just how organisms respond to different temperature regimes, but also how variation in local resource availability modifies those responses.

The Effect of Mycorrhizae on Plant Growth and Reproduction Varies with Soil Phosphorus and Developmental Stage

Abstract Determining the impact of both environmental variation and developmental stage on plant-mycorrhizal associations is important, as both can shift the association along the mutualism-parasitism continuum. This study examines the effect of phosphorus level on the response of Allium vineale to mycorrhizae across all plant life stages, including plant fecundity and the relative allocation of resources to three different reproductive modes (flowers, asexual underground offsets, and asexual aerial bulbils). For A. vineale, the impact of mycorrhizae varies significantly with life stage, as an early growth depression at 1 mo was reversed by 15 mo, resulting in mycorrhizal plants having larger bulbs over all P levels and producing more bulbils and larger offsets than nonmycorrhizal plants at lower P levels. However the presence of mycorrhizae did not affect the relative allocation of resources among the three reproductive modes. These results emphasize the importance of long-term studies of plant-mycorrhiz...

Life history and morphological variation in intraspecific seeder and resprouter populations of two species from rock outcrop vegetation in north-east New South Wales

The processes underlying differentiation of seeder and resprouter life histories were explored by studying changes in life history and morphological traits in intraspecific seeder and resprouter populations of the grass Entolasia stricta and shrub Keraudrenia hillii var. hillii from adjoining rock pavement and fringing woodland habitats. Population traits were sampled in the field and studied under controlled conditions in a randomised experimental design with two levels of population/habitat (seeder/rock outcrop and resprouter/woodland) and two levels of fertiliser (low and high). Life history traits reflecting rate of growth, relative allocation of resources to reproductive and vegetative growth and timing of events, as well as a selection of simple morphological traits were recorded. Generalised linear model analysis showed that population had a strong, significant effect on the majority of traits examined, particularly those relating to reproductive output. Many traits were also significantly responsive to nutrient, or induced plasticity, and significant interaction terms were very few. The two species exhibited parallel intraspecific changes in life history between habitats and traits recorded under experimental conditions were similar to those observed in the field. The populations from pavement shrubland produced a more compact shoot system, faster early shoot growth (E. stricta), more numerous flowers and more numerous and lighter seeds. In fringing woodland, both species produced a larger shoot system, slower early shoot growth and fewer and larger seeds. Significant intraspecific differences in population traits and correlation of population with habitat type indicated that the intraspecific seeder-resprouter populations of both species were ecotypes selected by habitat factors, most likely associated with the edaphic environment rather than fire regime variables.

배우자간 의사결정력에 따른 노부모로의 시간자원 이전

This paper investigates whether intra-household bargaining power affects couples` caregiving decisions during instances of competing parental demands for assistance. The primary focus is on examining how partners` bargaining power influences the relative allocation of time resources between parents and parents-in-law, assuming that children prefer to transfer caregiving resources toward their own parents over their parents-in-law. The findings in this study reject the bargaining theory that couple`s parental care behavior results from a bargaining process between the husband and the wife. More specifically, the results did not clearly show that children prefer to transfer caregiving resources toward their own parents over their parents-in-law. Decision-making power, measured by final decision-making authority, also failed to affect the relative care transfers.

HARM REDUCTION IS NOW THE MAINSTREAM GLOBAL DRUG POLICY

HARM REDUCTION IS NOW THE MAINSTREAM GLOBAL DRUG POLICY

Influence of Drought and Shade on Seedling Growth of Native and Invasive Trees in the Seychelles

ABSTRACTWe studied the growth of seedlings of native and invasive tree species from secondary tropical forests on Mahé (Seychelles). We were interested in whether native or invasive species are more drought‐tolerant, and therefore conducted a garden (pot) experiment comparing the growth of seedlings of five native and five invasive tree species under different light (7% and 60% transmittance) and water (natural and repeated drought stress) conditions. Differences in the responses of native and invasive species to these treatments were small. In both groups, mean relative growth rates were reduced only slightly by intermittent drought that caused wilting of leaves. However, invasive species produced clearly thinner leaves (high specific leaf area, SLA) and more root biomass than native species under high light, while these differences were small under low light. Native species performed better than invasive species under low light with low water availability. It appears that high phenotypic plasticity allows some fast‐growing invasive species to cope with water stress by adjusting the relative allocation of resources to aboveground and belowground structures under high light, while this strategy is not effective when both light and water resources are limiting. We conclude that water stress may reduce the invasibility of shaded habitats by fast‐growing invasive species, while water stress in unshaded habitats may have less effect on invasive species than previously recognized.

Gender variation and primary succession in a tropical woody plant, Antirhea borbonica (Rubiaceae)

Summary 1 Ecological context can significantly affect plant reproduction: in particular, differences in the relative allocation of resources to male and female function can contribute to gender variation. 2 We quantified variation in sex expression among populations of Antirhea borbonica , a sexually dimorphic woody pioneer species found both on young lava flows and in later stages of primary succession on the volcanic island of La Reunion. We also tested whether environmental conditions influence maternal fertility by experimentally manipulating resource levels in natural populations. 3 The polliniferous morph showed significant gender variation, from almost zero fruit production in pioneer populations to high fruit set, albeit of less than females, in late-succession. Repeated observations over 4 years showed that, even in pioneer populations, most polliniferous plants are capable of producing fruits. 4 A significant increase in fruit production by the polliniferous morph was observed after 2 years of resource supplementation in a pioneer population. 5 Sex ratios were close to 1 : 1 in all but one of 12 populations. Seeds and seedlings produced by the polliniferous morph in a late-succession population had significantly lower viability than those from females. These results indicate that there is strong selection against the maternal offspring produced by polliniferous plants and that, regardless of successional status, A. borbonica possesses a functionally dioecious sexual system. 6 The combination of multi-year surveys and experimental manipulation of resource availability provides evidence of phenotypic gender plasticity. This provides a novel illustration of how the heterogeneous environment of primary succession can influence trait variation.

Growth or reproduction? Resource allocation by female frogs Rana temporaria.

The decision how to allocate marginal resources to reproduction and growth can have important effects on associated life-history parameters as well as on population dynamics. In addition to showing variation among individuals in a population, such allocation rules may be either condition-dependent or fixed in different individuals. While many studies on anuran amphibians have focused on egg numbers and egg sizes in females of different sizes, virtually no data exist on the relative allocation of marginal resources to growth versus reproduction. In the laboratory, we therefore offered female common frogs ( Rana temporaria) low versus high food rations for a full reproductive cycle, and monitored their growth and later reproductive investment (egg number and egg size the following breeding season). Feeding rates had an effect both on female growth and on egg number and size. There was no trade-off found between the two forms of investment. A flexible allocation rule could not be supported as there was no significant effect of feeding rate on the relative allocation of resources to growth versus reproduction.

Size‐dependent sex allocation within flowers of the annual herb Clarkia unguiculata (Onagraceae): ontogenetic and among‐plant variation

The relative allocation of resources to male and female functions may vary among flowers within and among individual plants for many reasons. Several theoretical models of sex allocation in plants predict a positive correlation between the resource status of a flower or individual and the proportion of reproductive resources allocated to female function. These models assume that, independent of resource status, a negative correlation exists between male and female investment. Focusing on the allocation of resources within flowers, we tested these theoretical predictions and this assumption using the annual Clarkia unguiculata (Onagraceae). We also sought preliminary evidence for a genetic component to these relationships. From 116 greenhouse-cultivated plants representing 30 field-collected maternal families, multiple flowers and fruits per plant were sampled for gamete production, pollen : ovule ratio, seed number, ovule abortion, seed biomass/fruit, mean individual seed mass, and petal area. If sex allocation changes as predicted, then (1) assuming that flowers produced early have access to more resources than those produced later, basal flowers should exhibit a higher absolute and proportional investment in female function than distal flowers and (2) plants of high resource status (large plants) should produce flowers with a higher proportional investment in female function than those of low resource status. Within plants, variation in floral traits conformed to the first prediction. Among plants and families, no significant effects of plant size (dry stem biomass) on intrafloral proportional sex allocation were observed. We detected no evidence for a negative genetic correlation between male and female investment per flower, even when controlling for plant size.

Queen-Worker Conflict over Sexual Production and Colony Maintenance in Perennial Social Insects.

An important idea from kin selection theory as applied to life-history evolution in perennial insect societies suggests that potential conflict exists between the queen and workers over the relative allocation of resources to colony reproduction and colony growth. This prediction assumed a colony with one singly mated queen, sterile workers, and independent colony foundation by dispersing queens. We argue that this prediction is mistaken because queen and workers under these circumstances can only invest in sexuals (new queens and males) derived from the colony queen. Assuming population sex ratio equilibrium, potential conflict is absent because both parties maximize fitness by maximizing the colony's total output of these sexuals. However, a similar queen-worker conflict is predicted in facultatively polygynous species in which existing queens are superseded. We hypothesize that queens favor the production of relatively more new workers to prolong their lives as reproductives, whereas workers favor raising relatively more new queens as possible replacements. We tested this hypothesis using productivity data from the ant Leptothorax acervorum. As predicted, queen number and worker number were, respectively, positively and negatively associated with the investment ratio of new workers to new queens. These findings imply a queen-worker conflict over caste determination in ants.