Individual Resource Use Research Articles

Updating standardized unit costs from a societal perspective for health economic evaluation

The aim of this work was to update the 2015 unit costs (UC) for the monetary valuation of health-related resource use from a societal perspective for the years 2019 and 2020 in Germany. The update follows the methodology of Bock et al. 2015. Based on the newly established care levels, UC for care degree 1 to 5 are now provided. To account for change in price trends during the Covid-19 pandemic, average growth rates in UC are shown from 2011-2019 and compared to 2019-2020. Updates of UC for the outpatient medical sector, remedies and aids, hospitals, (in)formal care services, and rehabilitation for 2019 and 2020 are provided. The updated UC can be used as reference values for the monetary valuation of individual resource use in health economic evaluations in Germany.

Eğitim Yönetiminde Sürekliliğin Sürdürülebilirliğinin Eğitsel Araçlarının İncelenmesi

In this study, it is aimed to examine the educational tools of the sustainability of continuity in educational management. In this context, the works of leading scientists who stand out in the development of educational tools for the sustainability of continuity in educational management will be mentioned. As it is known, the main dynamics in the TQM approach are individuality, subjectivity, freedom and democracy. The criteria related to the quality of teaching are the field knowledge of instructors and administrators, the intellectual development levels of students, cooperation, the use of materials that support teaching, the classroom management skills of instructors, getting feedback from the student, encouraging students to learn independently, developing competent evaluation methods. There are working groups that produce alternative ideas about education in teaching organizations that practice TQM. In-service educational programs for corporate managers focus on creating a vision, ensuring environmental-institutional integrity, participatory management thinking, cooperation, teamwork, developing individual resources, motivation, problem solving, developing creativity and increasing productivity, competent managerial and instructional leadership. In this context, it is of great importance to redefine teaching in line with the dynamics of community development and to bring teaching organizations into a functional structure for the purpose. Teaching should be perceived as a collection of subjects that contain conditions that can meet the individual's curiosity for development and knowledge, creativity and productivity. The main condition for the establishment of this understanding is to be able to make competent use of individual resources on the teaching level. It is difficult to reach the intended level with authoritarian policies and understandings that alienate the community and the world. At this point, the flexible structuring model of TKI, which is open to development, is also suitable for the structure and functioning of educational organizations. Key Words: Educational Management, Continuity, Sustainability, Educational Tools

A Review of Power Co-Generation Technologies from Hybrid Offshore Wind and Wave Energy

Renewable energy resources such as offshore wind and wave energy are environmentally friendly and omnipresent. A hybrid offshore wind-wave energy system produces a more sustainable form of energy that is not only eco-friendly but also economical and efficient as compared to use of individual resources. The objective of this paper is to give a detailed review of co-generation technologies for hybrid offshore wind and wave energy. The proposed area of this review paper is based on the power conversions techniques, response coupling, control schemes for co-generation and complimentary generation, and colocation and integrated conversion systems. This paper aims to offer a systematic review to cover recent research and development of novel hybrid offshore wind-wave energy (HOWWE) systems. The current hybrid wind-wave energy structures lack efficiency due to their design and AC-DC-AC power conversion that need to be improved by applying an advanced control strategy. Thus, using different power conversion techniques and control system methodologies, the HOWWE structure can be improved and will be transferrable to the other hybrid models such as hybrid solar and wind energy. The state-of-the-art HOWWE systems are reviewed. Critical analysis of each method is performed to evaluate the best possible combination for development of a HOWWE system.

What a few hairs can tell us about the resource use of giant armadillos.

Understanding of resource requirements of vulnerable species is key for conservation planning. Here, we used stable carbon (δ13 C) and nitrogen isotopes (δ15 N) of hair from giant armadillos (Priodontes maximus) to understand individual resource use. We collected hair from 19 giant armadillos analyzing 34 samples from the Brazilian Pantanal and compared the resource use between sexes and age classes. We also assessed the relationship of isotopic values with individuals' body mass and the habitat type used. We observed a wide variation in resource use by giant armadillos, showing that individuals consume prey that feeds on distinct resources and occupies different habitat types, indicating that there is individual variation in foraging behavior. Most giant armadillos presented a mixed diet (C3 /C4 resources, forests/open areas), but a quarter of individuals had strictly C4 diets (open areas). Males are more prone to forage on C4 resources, presenting an isotopic niche 2.6-times larger than that of females. Subadults presented diets more associated with habitats with high arboreal cover (C3 resources, forests), while adults foraged more in open areas (C4 resources). This result is mirrored by the positive relationship between δ13 C values and body mass, suggesting that larger giant armadillos tend to feed more in open areas. We observed that δ13 C values decreased as individuals increased the use of habitats with high arboreal cover. We stress the importance of conserving the natural mosaic in the Pantanal landscape for the species persistence, given that giant armadillos require all habitat types to fulfill their dietary, spatial, and developmental needs.

No Effect of Early Adult Experience on the Development of Individual Specialization in Host-Searching Cabbage White Butterflies

Individuals in a population often use unique subsets of locally available resources, but we do not entirely understand how environmental context shapes the development of these specializations. In this study, we used ovipositing cabbage white butterflies (Pieris rapae) searching for host plants to test the hypothesis that early experience with an abundant resource can lead to later individual specialization. We first exposed naïve butterflies to one of three environments with different relative abundances of host plants of comparable nutritional quality, cabbage and radish. The next day, we observed butterflies from all treatments searching for hosts in a common environment where cabbage and radish were equally abundant. We predicted that the butterflies would preferentially visit the host plant that had been abundant during their previous experience, but instead found that butterflies from all experience treatments visited cabbage, a likely more visually salient host, more often than radish. In this experiment, behavioral plasticity in current conditions outweighed developmental experience in shaping individual resource use. We argue that these butterflies potentially respond to particularly salient search cues and that the discriminability of a resource may lead to specialization bias independent of early life experiences with abundant resources.

Management Efficiency: Necessity and Possibility of Assessing the Process and Result

The practice and theory of modern management associates the assessment of efficiency with the results of the company's work or changes in the level of use of individual resources. The criteria are results such as profit, profitability, labor productivity, the level of financial independence and others. We judge about the effectiveness of management by changes in these criteria. The number of criteria varies, and the results often show opposite conclusions about the level of effectiveness. This approach is not relevant in market conditions since the external environment, in which the company operates, remains beyond the assessment zone: with a shrinking market, profit may decrease but this is not evidence of deterioration in management. The second methodological problem is the lack of assessment of the management process itself as a set of certain actions. The purpose of the study was to develop a scientific approach to assessing the effectiveness of management in a competitive environment. The article presents a methodology for assessing efficiency not only in terms of results (management efficiency) but also actions (process efficiency). The research methodology is based on critical analysis and synthesis of theoretical and practical approaches to management assessment. The unity of the assessment of the management process and its results is the scientific novelty of the proposed methodology. The methodology was illustrated by the example of the Irkutsk Oil Company.

Between you and I: A portfolio theory of the circular economy

By using resources more circularly, individual resources users hope to contribute to a more eco-efficient and sustainable resource use. Whether resources are used sustainably is decided at the macro-level, raising the question if, as well as how, the efficient and circular use of resources at the micro-level adds up to their efficient and circular use on the macro-level. Currently, the link between the circular use of resources at micro- and macro-levels is under-theorized. The symbiotic relationship between individual resource users enables a reduction in the resource use at the macro-level. In this conceptual paper, we argue that an analogous link exists in finance where desirable investment return is linked to undesirable investment risk, and that via the generation of efficient portfolios, individual risks are at least partially diversified away. As our main contribution, we theorize the circular economy, both in its perfect and imperfect forms, using modern portfolio theory. Our theory identifies the drivers of circular resource use and shows under which conditions individual resource use contributes to the circular use of resources.

Predator community and resource use jointly modulate the inducible defense response in body height of crucian carp.

Phenotypic plasticity can be expressed as changes in body shape in response to environmental variability. Crucian carp (Carassius carassius), a widespread cyprinid, displays remarkable plasticity in body morphology and increases body depth when exposed to cues from predators, suggesting the triggering of an antipredator defense mechanism. However, these morphological changes could also be related to resource use and foraging behavior, as an indirect effect of predator presence. In order to determine whether phenotypic plasticity in crucian carp is driven by a direct or indirect response to predation threat, we compared twelve fish communities inhabiting small lakes in southeast Norway grouped by four categories of predation regimes: no predator fish, or brown trout (Salmo trutta), perch (Perca fluviatilis), or pike (Esox lucius) as main piscivores. We predicted the body shape of crucian carp to be associated with the species composition of predator communities and that the presence of efficient piscivores would result in a deeper body shape. We use stable isotope analyses to test whether this variation in body shape was related to a shift in individual resource use—that is, littoral rather than pelagic resource use would favor the development of a specific body shape—or other environmental characteristics. The results showed that increasingly efficient predator communities induced progressively deeper body shape, larger body size, and lower population densities. Predator maximum gape size and individual trophic position were the best variables explaining crucian carp variation in body depth among predation categories, while littoral resource use did not have a clear effect. The gradient in predation pressure also corresponded to a shift in lake productivity. These results indicate that crucian carp have a fine‐tuned morphological defense mechanism against predation risk, triggered by the combined effect of predator presence and resource availability.

Diet of Andean bears in Tamá National Natural Park, Colombia

Diet is among the most important and basic ecological aspects of a species. Information on diet composition, seasonality, and spatial variation is necessary for adequate ecological understanding and therefore conservation. Andean bears (Tremarctos ornatus) have been poorly studied across their distribution, and especially in Colombia; therefore, most ecological aspects remain unknown. The objective of this work was to assess Andean bears' diet and seasonality in order to contribute to the knowledge, management, and conservation of the species in northeastern Colombia. Between June 2012 and May 2015, 83 linear transects were surveyed at least once in 35 localities in Tama National Natural Park in search of fresh bear scats. Transects covered all land-cover types in the park proportionately. We collected 148 scats for diet analyses, and compared all items found with reference material. We assessed diet contents in terms of frequency of occurrence and compared across seasons, elevation, and land-cover types. Overall, plant items showed the greatest frequency of occurrence in the scats (96.8%), followed by mammals (6.7%) and insects (6.7%); we found this pattern for all land-cover types and all elevation ranges. We found seasonal variation and differences in use of some food items. We found the largest niche breadth for the dry season (B = 7.10) compared with the wet season (B = 4.14). Plant items were more frequently consumed during both dry and rainy seasons (0.78 ± 0.16 and 0.82 ± 0.11, respectively) and bromeliads were the most important food item during both seasons (0.32 and 0.46). This variation probably is related to the structure, phenology, and composition of vegetation in the area. More data are needed for estimating foraging preferences and their relationship with food availability and other aspects related to behavior and individual resource use.

Relationship between individual metabolic rate and patch departure behaviour: evidence from aquatic gastropods

Individual energy requirements are tightly related to individual resource use and by extension of space‐use patterns and other traits at higher levels of the ecological hierarchy. However, there is still little experimental evidence linking individual energetics and space‐use behaviour. Individual energy requirements scale mainly with body size and temperature, but these do not explain all individual variation. Therefore, studies focused on inter individual variation in resource and space use behaviour can be used to frame foraging dynamics in an energy perspective. We empirically tested the hypothesis of a relationship between individual energetics and patch departure behaviour using as model organisms four small species (body mass ranging from 0.4 to 14 mg AFDW) of aquatic gastropods strongly differing in adult size: Galba truncatula, Bithynia tentaculata, Theodoxus fluviatilis and Ecrobia ventrosa (in descending order of size). Motility tests were performed in controlled microcosm conditions. The tests were designed to classify the specimens as either low motility (not inclined to abandon the patch) or high motility (likely to abandon the patch). The tests entailed measuring the propensity of the individuals to abandon a limited resource patch (2 g DW of conditioned Phragmites australis leaves) within a given amount of time (24 h) when foraging with conspecifics under conditions where competition for food is expected to increase over time due to resource depletion. The individual standard metabolic rate of the tested specimens was measured via open flow respirometry and compared across motility classes at intra‐ and interspecific level. At both levels, we observed that individuals with higher standard metabolic rates were more inclined to abandon the patch. This finding establishes a link between foraging theory and competitive coexistence mechanisms.

ТЕОРИЯ, МЕТОДОЛОГИЯ И ЭВОЛЮЦИЯ ПОНЯТИЙ ИННОВАЦИОННОГО РАЗВИТИЯ РЫНОЧНОЙ ЭКОНОМИКИ

This article includes the results of the authors' research on the theory, methodology and evo-lution of the concepts of an innovative economy in market conditions. innovation is based on the satisfaction of certain social needs, but at the same time, an increase in the efficiency of the use of individual resources or an increase in the efficiency of individual production units, or an increase in the efficiency of an enterprise as a whole as a result of the introduction of an innovation and receipt of an innovation does not always happen.

Lifelong foraging and individual specialisation are influenced by temporal changes of resource availability

Resource availability largely determines the distribution and behaviour of organisms. In plant–pollinator communities, availability of floral resources may change so rapidly that pollinator individuals can benefit from switching between multiple resources, i.e. different flowering plant species. Insect pollinator individuals of a given generation often occur in different time windows during the reproductive season. This temporal variation in individual occurrences, together with the rapidly changing resource availability, may lead individuals of the same population to encounter and use different resources, resulting in an apparent individual specialisation. We hypothesized, that 1) individual pollinators change their resource use (flower visitation) during their lifetime according to the changing availability of floral resources, and that 2) temporal variation in individual occurrences of pollinators and in resource availability will partly explain individual specialisation. To test these hypotheses, we observed flower visitations of individually marked clouded Apollo butterflies Parnassius mnemosyne during one reproductive season. We found temporal changes in lifetime individual resource use that followed the changes in resource availability, indicating that butterflies can adjust foraging to varying resource availability. Individuals differed considerably in their resource use. This variation was partly explained by temporal variation in both floral resource availability and temporal occurrence of individual butterflies. We suggest the butterfly as a sequential specialist, i.e. short‐term specialist and long‐term generalist. This foraging plasticity can be essential for short‐living insect pollinators in rapidly changing environments. Although flowering dynamics do not fully explain the variability in foraging, our results highlight the importance of temporal dimension in resource use studies. Ultimately, the relative pace of environmental change compared to individual lifespan may be a key factor in resource use plasticity.

Direct health and residential care costs of people living with dementia in Australian residential aged care.

ObjectivesThis analysis estimates the whole‐of‐system direct costs for people living with dementia in residential care by using a broad health and social care provision perspective and compares it to people without dementia living in residential care.MethodsData were collected from 541 individuals living permanently in 17 care facilities across Australia. The annual cost of health and residential care was determined by using individual resource use data and reported by the dementia status of the individuals.ResultsThe average annual whole‐of‐system cost for people living with dementia in residential care was approximately AU$88 000 (US$ 67 100) per person in 2016. The cost of residential care constituted 93% of the total costs. The direct health care costs were comprised mainly of hospital admissions (48%), pharmaceuticals (31%) and out‐of‐hospital attendances (15%). While total costs were not significantly different between those with and without dementia, the cost of residential care was significantly higher and the cost of health care was significantly lower for people living with dementia.ConclusionThis study provides the first estimate of the whole‐of‐system costs of providing health and residential care for people living with dementia in residential aged care in Australia using individual level health and social care data. This predominantly bottom‐up cost estimate indicates the high cost associated with caring for people with dementia living permanently in residential care, which is underestimated when limited cost perspectives or top‐down, population costing approaches are taken.

Нематеріальні ресурси адаптації сільського населення

The transformation processes, which continue in Ukraine for more than 20 years are associated with significant changes in the system of orientation of the population, including changing priorities in their needs, interests of society and the state. The basic condition for the country to reach the real sustainable development, according to many scientists, is a successful adaptation of the population, which is the development, by a sufficient number of people, of effective models of socio-economic behavior based on the use of individual resources. The subject of our study are non-material resources of the rural population, because they cannot be lost or alienated as a result of external influences and social experiments that occurred in the 90s of the last century and, unfortunately, have cyclically repeated. Under non-material resources we consider educational characteristics, professional qualification skills, informational and cultural opportunities, the peasants' connections and non-financial benefits of temporary labor migration. The study found that the information and cultural resources of the rural population are the scarcest. Long-term constraints to the use of modern information technologies such as the Internet, computer programs and databases, specialized periodicals, and visiting cultural institutions leads to mental-and-cultural and cognitive deprivation. Insufficiency or lack of information inevitably leads to its distortion and causes erroneous or inadequate decision-making, and the farmers' slow adaptation to rapidly changing conditions. Theoretical analysis of the development of relations among the rural population demonstrates the unilateralism of the resource development. There is a well-established network of horizontal interaction (family, neighbors) and vertical network relationships are almost completely absent. Any kind of care inaccessible to the rural population, peasants' representation in government and political movements are of local character. In order to diversify the risks associated with the implementation of an adaptation strategy, it is advisable to supplement the hopes for own assets with external interaction. It is proved that the educational and professional-qualification resources, provided their quality improvement and modernization, in the short term, will allow the rural population to build effective adaptation oriented behavioral strategies. Level of education meets, by certain criteria, the general European levels, while the use of this resource, in today's realities, is complicated by the inconsistency in orientation, profile, and quality of previous education with the requirements of the emerging labor market. Modernization of knowledge, institutionalization of new forms and methods of teaching, and the widespread introduction of lifelong education will positively influence the rapid evaluation of particular features of external changes and development of a rational adaptation strategy. The non-material adaptation resources include the effects of temporary labor migration. Without idealizing the process, and focusing only positive features in terms of adaptation of the population to the changing conditions, we found that working in more developed countries enhances the outlook, the formation of a new way of life, the transformation of priorities, and creating new needs for its own existence and livelihood of their families. Further studies will be directed to identify links between adaptation to available resources, including intangible ones, and improving (worsening) economic and situation of the farmers.

Diet–demography relationships in a long‐lived predator: from territories to populations

Understanding the mechanisms that shape animal population dynamics is of fundamental interest in ecology, evolution and conservation biology. Food supply is an important limiting factor in most animal populations and may have demographic consequences. Optimal foraging theory predicts greater consumption of preferred prey and less diet diversity when food is abundant, which may benefit key fitness parameters such as productivity and survival. Nevertheless, the correspondence between individual resource use and demographic processes in populations of avian predators inhabiting large geographic areas remains largely unexplored, particularly in complex ecosystems such as those of the Mediterranean basin. Based on a long‐term monitoring program of the diet and demography of Bonelli's eagleAquila fasciatain western Europe, here we test the hypothesis that a predator's diet is correlated to its breeding productivity and survival at both the territorial and population levels, and ultimately to its population growth rate. At the territorial level, we found that productivity increased with greater consumption of European rabbitsOryctolagus cuniculus, the Bonelli's eagle's preferred prey, and pigeons, an important alternative prey for this predator. The survival of territorial pairs was negatively affected by higher diet diversity, which probably reflected the inability to find sufficient high quality prey. Diet effects at the population level were similar but more noticeable than at the territorial level, i.e. a greater consumption of rabbits, together with lesser consumption of small‐to‐medium avian species (‘other birds’; non‐preferred prey), increased productivity, while greater diet diversity and lower consumption of rabbits was associated with reduced survival and population growth rate. Overall, our study illustrates how the diet of a predator species can be closely related to key individual vital rates, which, in turn, leave a measurable fingerprint on population dynamics within and among populations across large spatial scales.

Transverse Sinus Stenting for Pseudotumor Cerebri: A Cost Comparison with CSF Shunting

Transverse sinus venous stent placement has been shown to lower intracranial pressure in patients with venogenic pseudotumor cerebri and to reverse, or at least stabilize, its symptoms and signs. There have been no studies comparing the cost of venous stenting with the time-honored treatment for pseudotumor cerebri-CSF shunting. The purpose of this study was to compare the cost of trasverse sinus stenting versus CSF shunting for the treatment of pseudotumor cerebri. This work was a retrospective cost analysis of individual resource use in 86 adults who were stented for pseudotumor cerebri during a 12-year period compared with resource use in 110 children who were shunted for hydrocephalus during a 3-year period. There was no significant difference between the cost of inserting an initial venous stent ($13,863 ± 4890) versus inserting an initial CSF shunt ($15,797 ± 5442) (P = .6337) or between inserting an additional venous stent ($9421 ± 69) versus revising a CSF shunt ($10,470 ± 1245) (P = .4996). There were far fewer additional venous stent insertions per patient than there were subsequent CSF shunt revisions; 87% of stents placed required just 1 stent procedure, whereas only 45% of shunts required 1 shunt procedure. The main cause of the cost difference was the need for repeated revisions of the shunts, especially when they became infected-24 instances of a total 143 shunt procedures (16.8%) at an average cost of $84,729, approximately 5 times the cost of an initial shunt insertion. Venous stenting costs significantly less per 100 procedures than does CSF shunting, due largely to the high cost of treating shunt infections and the need for repeated shunt revisions.

Temporal consistency and individual specialization in resource use by green turtles in successive life stages

Not all individuals in a population use the same subset of dietary and habitat resources. Patterns of individual specialization have been documented in an increasing number of organisms, but often without an associated time scale over which niche specialization was observed. We examined the patterns in individual resource use through time and in relation to the population with metrics of temporal consistency and degree of individual specialization. We used stable isotope analysis of carbon and nitrogen in successive subsections of scute tissue from the carapace to compare foraging patterns in three successive life stages of the green turtle (Chelonia mydas). Temporal consistency was measured as the mean within-individual variation in stable isotope values through time, whereas the degree of individual specialization was a ratio of the individual variation to that of the population. The distinction between these two parameters is important, as the metric of temporal consistency quantifies the regularity of individual resource use, and the degree of individual specialization indicates what proportion of the population niche an average individual uses. The scute record retains a chronological history of resource use and was estimated to represent a minimum 0.8 years in juveniles to a maximum of 6.5 years in adults. Both temporal consistency and individual specialization varied significantly among life stages. Adults were highly consistent in resource use through time and formed a generalist population with individual specialists maintaining long-term patterns in resource use. Oceanic and neritic juvenile life stages exhibited less temporal consistency in resource use with less individual specialization than adults. These observations are important when considering the ecological roles filled by green turtles in each life stage; also, individual differences in resource use may result in differential fitness consequences.

Estimating the costs of ongoing care for adolescents with attention-deficit hyperactivity disorder

Attention-deficit hyperactivity disorder (ADHD) is associated with increased use of health, social and education services. There is a lack of data to quantify the economic burden of ADHD in the UK. The aim of this study was to estimate additional education, health and social care costs amongst adolescents in the UK diagnosed with ADHD. Participants were 143, 12- to 18-year-olds from the Cardiff longitudinal ADHD study. Service use relating to mental health over the previous year was measured using the children's service interview. Individual resource use was combined with unit cost data, from national sources, to calculate costs per patient and subsequently the mean cost per patient. Mean costs, 95% confidence intervals and median use were calculated using nonparametric bootstrapping methods. The mean cost per adolescent for NHS, social care and education resources used in a 12-month period related to ADHD was £5,493 (£4,415.68, £6,678.61) in 2010 prices and the median was £2,327. Education and NHS resources accounted for approximately 76 and 24%, respectively. Estimated annual total UK costs are £670 million. The additional costs to the NHS and education system of treating adolescents remain substantial for several years after the initial ADHD diagnosis. There exists a need to develop and evaluate early interventions which have the potential to reduce the longer-term burden, particularly on education resource use.

Morphological distance and inter‐nest distance account for intra‐specific prey overlap in digger wasps (Hymenoptera: Crabronidae)

AbstractAlthough inter‐individual diet variation is common in predatory wasp populations, the factors accounting for such variation are still largely unknown. Here, we asked if paired diet dissimilarity in three species of digger wasps correlates with morphological distance and inter‐nest distance, two factors previously linked to diet partitioning in vertebrates. Results sharply differed among species and generations. All sampled populations showed significant inter‐individual diet variation for prey taxa, but only in half of the cases for prey size. In one generation of two species [Bembix zonata Klug and Stizus continuus (Klug)], similar‐sized wasps had similar prey taxonomic spectra (and for S. continuus also similar prey size spectra), a phenomenon which probably reduces intra‐specific competition. In addition, B. zonata females nesting closer to each other had more similar prey taxonomic spectra, suggesting that distant females probably hunt on different patches that harbour different prey species. For the females of a further species (Bembix merceti Parker), pairwise size difference and inter‐nest distance did not affect prey dissimilarity. Both morphological distance and inter‐nest distance are potentially important in shaping the overlap of individual resource use in wasps, though probably only in certain conditions such as a highly clumped distribution of nests and size‐related constraints on prey selection.

Isometric size-scaling of metabolic rate and the size abundance distribution of phytoplankton.

The relationship between phytoplankton cell size and abundance has long been known to follow regular, predictable patterns in near steady-state ecosystems, but its origin has remained elusive. To explore the linkage between the size-scaling of metabolic rate and the size abundance distribution of natural phytoplankton communities, we determined simultaneously phytoplankton carbon fixation rates and cell abundance across a cell volume range of over six orders of magnitude in tropical and subtropical waters of the Atlantic Ocean. We found an approximately isometric relationship between carbon fixation rate and cell size (mean slope value: 1.16; range: 1.03-1.32), negating the idea that Kleiber's law is applicable to unicellular autotrophic protists. On the basis of the scaling of individual resource use with cell size, we predicted a reciprocal relationship between the size-scalings of phytoplankton metabolic rate and abundance. This prediction was confirmed by the observed slopes of the relationship between phytoplankton abundance and cell size, which have a mean value of -1.15 (range: -1.29 to -0.97), indicating that the size abundance distribution largely results from the size-scaling of metabolic rate. Our results imply that the total energy processed by carbon fixation is constant along the phytoplankton size spectrum in near steady-state marine ecosystems.