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1.
Semin Cell Dev Biol ; 155(Pt A): 3-9, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36858897

RESUMO

Maintaining proper metabolite levels in a complex metabolic network is crucial for maintaining a high flux through the network. In this paper, we discuss major regulatory mechanisms over the Calvin Benson Cycle (CBC) with regard to their roles in conferring homeostasis of metabolite levels in CBC. These include: 1) Redox regulation of enzymes in the CBC on one hand ensures that metabolite levels stay above certain lower bounds under low light while on the other hand increases the flux through the CBC under high light. 2) Metabolite regulations, especially allosteric regulations of major regulatory enzymes, ensure the rapid up-regulation of fluxes to ensure sufficient amount of triose phosphate is available for end product synthesis and concurrently avoid phosphate limitation. 3) A balanced activities of enzymes in the CBC help maintain balanced flux through CBC; some innate product feedback mechanisms, in particular the ADP feedback regulation of GAPDH and F6P feedback regulation of FBPase, exist in CBC to achieve such a balanced enzyme activities and hence flux distribution in the CBC for greater photosynthetic efficiency. Transcriptional regulation and natural variations of enzymes controlling CBC metabolite homeostasis should be further explored to maximize the potential of engineering CBC for greater efficiency.


Assuntos
Fosfatos , Fotossíntese , Fotossíntese/fisiologia
2.
Proc Natl Acad Sci U S A ; 120(24): e2218828120, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37276416

RESUMO

The foundations of today's societies are provided by manufactured capital accumulation driven by investment decisions through time. Reconceiving how the manufactured assets are harnessed in the production-consumption system is at the heart of the paradigm shifts necessary for long-term sustainability. Our research integrates 50 years of economic and environmental data to provide the global legacy environmental footprint (LEF) and unveil the historical material extractions, greenhouse gas emissions, and health impacts accrued in today's manufactured capital. We show that between 1995 and 2019, global LEF growth outpaced GDP and population growth, and the current high level of national capital stocks has been heavily relying on global supply chains in metals. The LEF shows a larger or growing gap between developed economies (DEs) and less-developed economies (LDEs) while economic returns from global asset supply chains disproportionately flow to DEs, resulting in a double burden for LDEs. Our results show that ensuring best practice in asset production while prioritizing well-being outcomes is essential in addressing global inequalities and protecting the environment. Achieving this requires a paradigm shift in sustainability science and policy, as well as in green finance decision-making, to move beyond the focus on the resource use and emissions of daily operations of the assets and instead take into account the long-term environmental footprints of capital accumulation.

3.
Am Nat ; 203(2): 254-266, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38306278

RESUMO

AbstractDespite avid interest in life history trade-offs and the costs of reproduction, evidence that increased parental allocation reduces subsequent breeding productivity is mixed. This uncertainty may be attributable to environmental heterogeneity in space and time, necessitating experiments across a range of ecological contexts. Over three breeding seasons, we cross-fostered clutches between nests to manipulate incubation duration in a wild population of Carolina wrens, a species in which only females incubate, to test for a cost of incubation on current and future reproduction. Prolonged incubation affected maternal productivity in a manner dependent on the current environment and initial investment in eggs, suggesting that incubation is optimized according to other components of reproduction and individual quality. Effects of incubation duration on foster nestling condition varied between years, being costly in one, beneficial in another, and neutral in the third. The proportion of young fledged, females' probability of breeding again within seasons, and subsequent clutch sizes all declined with increasing incubation effort-effects that became more pronounced as seasons progressed. Therefore, costs of incubation were almost entirely dependent on maternal quality and environmental variation, illustrating the importance of conducting experiments across a range of environmental settings for understanding the costs of reproduction and evolution of life histories.


Assuntos
Aves Canoras , Animais , Feminino , Reprodução , Probabilidade , Estações do Ano , Incerteza
4.
Proc Biol Sci ; 291(2016): 20240054, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38351799

RESUMO

In males, large testes size signifies high sperm production and is commonly linked to heightened sperm competition levels. It may also evolve as a response to an elevated risk of sperm depletion due to multiple mating or large clutch sizes. Conversely, weapons, mate or clutch guarding may allow individuals to monopolize mating events and preclude sperm competition, thereby reducing the selection of large testes. Herein, we examined how paternal care, sexual size dimorphism (SSD), weaponry and female fecundity are linked to testes size in glassfrogs. We found that paternal care was associated with a reduction in relative testes size, suggesting an evolutionary trade-off between testes size and parenting. Although females were slightly larger than males and species with paternal care tended to have larger clutches, there was no significant relationship between SSD, clutch size and relative testes size. These findings suggest that the evolution of testes size in glassfrogs is influenced by sperm competition risk, rather than sperm depletion risk. We infer that clutch guarding precludes the risk of fertilization by other males and consequently diminishes selective pressure for larger testes. Our study highlights the prominent role of paternal care in the evolution of testes size in species with external fertilization.


Assuntos
Poder Familiar , Testículo , Humanos , Masculino , Feminino , Animais , Sêmen , Espermatozoides/fisiologia , Reprodução , Comportamento Sexual Animal/fisiologia
5.
J Exp Zool B Mol Dev Evol ; 342(2): 101-105, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38291725

RESUMO

Embryos of Ilyanassa obsoleta (from Massachusetts and Florida) and Phrontis vibex (from Florida) were exposed to temperatures from 33 to 37°C. In both species, very young embryos are especially sensitive to thermal stress. Brief early heat shock did not disturb spiral cleavage geometry but led to variable, typically severe defects in larval morphogenesis and tissue differentiation. In Ilyanassa but not P. vibex, early heat shock resulted in immediate slowing or arrest of interphase progression during early cleavage. This reversible arrest was correlated with improved prognosis for larval development and (in Massachusetts snails, at least) depended on parental acclimation to warm temperature (~25.5°C). Embryos from Massachusetts snails housed at lower temperature (16°C) exhibited cytokinesis failure when briefly incubated at 33°C during early cleavage, and tissue differentiation failure during incubation at 33°C begun at later stages. This preliminary study reveals a case in which stress-conditioned parents may endow embryos with protection against potentially lethal thermal stress during the most vulnerable stages of life.


Assuntos
Hipertermia Induzida , Caramujos , Animais , Morfogênese , Temperatura , Aclimatação
6.
Osteoporos Int ; 35(6): 951-969, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38300316

RESUMO

Fracture liaison services (FLS) have been proven clinically effective and cost-effective in preventing subsequent fractures among patients with an existing fragility fracture. Little is known about their monetary benefits such as their return on investment (ROI). This systematic review aimed to investigate the ROI of FLS and identify the FLS characteristics with better ROI. Studies on the cost-effectiveness of FLS published between January 2000 and December 2022 were searched from MEDLINE, EMBASE, PubMed, and Cochrane Central. Two independent reviewers conducted study selection and data extraction. ROI was calculated based on the difference between monetary benefits and FLS costs divided by the FLS costs. Subgroup analysis of ROI was performed across FLS types and FLS design details. A total of 23 FLS were included in this review. The majority of them were targeting patients aged over 50 years having fractures without identified sites. The mean ROI of these FLS was 10.49 (with a median ROI of 7.57), and 86.96% of FLS had positive ROI. FLS making treatment recommendations yielded the highest ROI (with a mean ROI of 18.39 and a median of 13.60). Incorporating primary care providers (with a mean ROI of 16.04 and a median of 13.20) or having them as program leaders (with a mean ROI of 12.07 and a median of 12.07) has demonstrated a high ROI. FLS for specific fracture sites had great monetary return. Intensive FLS such as type A and B FLS programs had higher ROI than non-intensive type C and D FLS. This review revealed a 10.49-fold monetary return of FLS. Identified characteristics contributing to greater economic return informed value-for-money FLS designs. Findings highlight the importance of FLS and the feasibility of expanding their contribution in mitigating the economic burden of osteoporotic fracture and are conducive to the promotion of FLS internationally.


Assuntos
Análise Custo-Benefício , Fraturas por Osteoporose , Humanos , Fraturas por Osteoporose/prevenção & controle , Fraturas por Osteoporose/economia , Custos de Cuidados de Saúde/estatística & dados numéricos , Prevenção Secundária/organização & administração , Prevenção Secundária/economia
7.
Cytotherapy ; 26(7): 672-680, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38483363

RESUMO

BACKGROUND AIMS: To better understand the attitudes and behaviors of investors involved in funding cell and gene therapy (CGT) businesses, the Business Development and Finance) subcommittee of International Society for Cell and Gene Therapy, in collaboration with Truist Securities, conducted a broad survey of the investment community in late 2021. METHODS: This survey follows a similar study that this group executed in 2018, and the longitudinal comparisons between the two time periods provide insights into how investor behavior in the CGT field has evolved. RESULTS: The vast majority of investor respondents are specialist biotech investors who are primarily active in deploying capital in North America and Europe. There was a notable increase in the proportion of investors actively deploying capital in China and Japan between 2018 and 2021. The percentage of respondents' portfolios dedicated to CGT companies has also increased in this period, reflecting a noteworthy trend in the therapeutic landscape. CONCLUSIONS: Clinically significant data remain the dominant force behind investment decisions, whereas competition from other drug modalities has now emerged as the most-cited barrier to making a CGT investment, eclipsing safety concerns as the most significant barrier to investment in 2018. Concerns around manufacturing and scale-up have also increased in prominence amongst the investment community. Gene-editing technologies are attracting investors as the most compelling new CGT technology. This survey also revealed that most investors expect to increase their level of investment in allogeneic technologies relative to autologous products in the coming years.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Terapia Genética , Investimentos em Saúde , Humanos , Terapia Genética/economia , Terapia Genética/métodos , Investimentos em Saúde/economia , Terapia Baseada em Transplante de Células e Tecidos/economia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Inquéritos e Questionários , Biotecnologia/economia , Biotecnologia/métodos
8.
J Evol Biol ; 37(11): 1378-1385, 2024 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-39352263

RESUMO

Animal nests provide a beneficial environment for offspring development and as such, contribute to fitness. Gathering and transporting materials to construct nests is energetically costly, but the life history trade-offs associated with the types of nests built are largely unknown. Who contributes to building the nest could also mediate these trade-offs, as building a nest as a couple is expected to be less costly per individual than building alone. Using a comparative analysis of 227 songbird species globally, we found a fecundity cost associated with the type of nest a species builds. Species that build domed nests produce fewer broods per year than species building cups or platforms. Dome nesting species also have larger clutch sizes than open nesting species, but only when the nest is built by a couple and not when females build nests alone. This suggests that building domed nests represents a trade-off with investment in young, especially when females are solely responsible for nest building. More broadly, our results could explain macroevolutionary patterns, such as the recent finding that females, building on their own, more often build open cups rather than domed nests.


Assuntos
Tamanho da Ninhada , Fertilidade , Comportamento de Nidação , Animais , Feminino , Aves Canoras/fisiologia , Masculino
9.
Int J Behav Nutr Phys Act ; 21(1): 127, 2024 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-39506753

RESUMO

BACKGROUND: Between 2006 and 2016 the prevalence of overweight and obesity among children and adolescents aged 5-19 years in Peru increased from 22.7 to 27.0%. This investment case quantifies the economic impacts of childhood and adolescent overweight and obesity in Peru. It identifies and quantifies the potential impact of a set of new or expanded interventions that can strengthen current national efforts to prevent and reduce child and adolescent overweight and obesity. METHODS: A deterministic Markov cohort model with a societal cost perspective estimated reductions in mortality and morbidity from implementing interventions to prevent and reduce child and adolescent overweight and obesity and the impact in savings in healthcare costs and gains in wages and productivity. Interventions identified through a review of published literature includes a school-based social marketing campaign, exclusive breastfeeding promotion and support, a healthy food and drink policy for school premises, and a 20% subsidy on fruits and vegetables for people living below the national poverty line. The return on investment (ROI) was calculated along with the estimated cost savings associated with the interventions. Analysis was conducted to test ROI sensitivity to changes in the key parameters and assumptions. RESULTS: Between 2025 and 2092, the expected combined direct and indirect healthcare costs attributable to child and adolescent overweight and obesity in Peru are 210.6 billion USD. The direct healthcare costs are 1.8 billion USD, and the indirect costs are 208.8 billion USD. Expected savings for all interventions combined is 13.9 billion USD with a per-person savings of 12,089.8 USD. The expected ROI of the four interventions combined is 39.3 USD (30-years), 64.6 USD (50-years), and 164.1 USD (66-years) per one USD invested. CONCLUSIONS: The overweight and obesity epidemic among children and adolescents in Peru requires wide-ranging and expanded implementation of policies to achieve long-term reductions in prevalence. This study's findings show that the four priority interventions have high ROIs and can be used to guide policy to address the complex interplay of factors that contribute to the obesogenic environment.


Assuntos
Obesidade Infantil , Humanos , Adolescente , Criança , Peru , Obesidade Infantil/prevenção & controle , Pré-Escolar , Feminino , Masculino , Promoção da Saúde/métodos , Adulto Jovem , Análise Custo-Benefício , Cadeias de Markov , Sobrepeso/prevenção & controle , Prevalência , Custos de Cuidados de Saúde/estatística & dados numéricos
10.
Int J Behav Nutr Phys Act ; 21(1): 18, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38373957

RESUMO

Numerous research methodologies have been used to examine food environments. Existing reviews synthesizing food environment measures have examined a limited number of domains or settings and none have specifically targeted Canada. This rapid review aimed to 1) map research methodologies and measures that have been used to assess food environments; 2) examine what food environment dimensions and equity related-factors have been assessed; and 3) identify research gaps and priorities to guide future research. A systematic search of primary articles evaluating the Canadian food environment in a real-world setting was conducted. Publications in English or French published in peer-reviewed journals between January 1 2010 and June 17 2021 and indexed in Web of Science, CAB Abstracts and Ovid MEDLINE were considered. The search strategy adapted an internationally-adopted food environment monitoring framework covering 7 domains (Food Marketing; Labelling; Prices; Provision; Composition; Retail; and Trade and Investment). The final sample included 220 articles. Overall, Trade and Investment (1%, n = 2), Labelling (7%, n = 15) and, to a lesser extent, Prices (14%, n = 30) were the least studied domains in Canada. Among Provision articles, healthcare (2%, n = 1) settings were underrepresented compared to school (67%, n = 28) and recreation and sport (24%, n = 10) settings, as was the food service industry (14%, n = 6) compared to grocery stores (86%, n = 36) in the Composition domain. The study identified a vast selection of measures employed in Canada overall and within single domains. Equity-related factors were only examined in half of articles (n = 108), mostly related to Retail (n = 81). A number of gaps remain that prevent a holistic and systems-level analysis of food environments in Canada. As Canada continues to implement policies to improve the quality of food environments in order to improve dietary patterns, targeted research to address identified gaps and harmonize methods across studies will help evaluate policy impact over time.


Assuntos
Abastecimento de Alimentos , Canadá , Humanos , Rotulagem de Alimentos/métodos , Comércio , Meio Ambiente , Marketing/métodos , Alimentos
11.
J Anim Ecol ; 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39473289

RESUMO

In its initial form, the expensive son hypothesis postulates that sons from male-biased sexually dimorphic species require more food during growth than daughters, which ultimately incur fitness costs for mothers predominantly producing and rearing sons. We first dissect the evolutionary framework in which the expensive son hypothesis is rooted, and we provide a critical reappraisal of its differences from other evolutionary theories proposed in the field of sex allocation. Then, we synthesize the current (and absence of) support for the costs of producing and rearing sons on maternal fitness components (future reproduction and survival). Regarding the consequences in terms of future reproduction, we highlight that species with pronounced sexual size dimorphism display a higher cost of sons than of daughters on subsequent reproductive performance, at least in mammals. However, in most studies, the relative fitness costs of producing and rearing sons and daughters can be due to sex-biased maternal allocation strategies rather than differences in energetic demands of offspring, which constitutes an alternative mechanism to the expensive son hypothesis stricto sensu. We observe that empirical studies investigating the differential costs of sons and daughters on maternal survival in non-human animals remain rare, especially for long-term survival. Indeed, most studies have investigated the influence of offspring sex (or litter sex ratio) at year T on survival at year T + 1, and they rarely provide a support to the expensive son hypothesis. On the contrary, in humans, most studies have focused on the relationship between proportion of sons and maternal lifespan, but these results are inconsistent. Our study highlights new avenues for future research that should provide a comprehensive view of the expensive son hypothesis, by notably disentangling the effects of offspring behaviour from the effect of sex-specific maternal allocation. Moreover, we emphasize that future studies should also embrace the mechanistic side of the expensive son hypothesis, largely neglected so far, by deciphering the physiological pathways linking son's production to maternal health and fitness.

12.
Am J Bot ; 111(1): e16260, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38031482

RESUMO

PREMISE: Herbivore pressure can vary across the range of a species, resulting in different defensive strategies. If herbivory is greater at lower latitudes, plants may be better defended there, potentially driving a latitudinal gradient in defense. However, relationships that manifest across the entire range of a species may be confounded by differences within genetic subpopulations, which may obscure the drivers of these latitudinal gradients. METHODS: We grew plants of the widespread perennial grass Panicum virgatum in a common garden that included genotypes from three genetic subpopulations spanning an 18.5° latitudinal gradient. We then assessed defensive strategies of these plants by measuring two physical resistance traits-leaf mass per area (LMA) and leaf ash, a proxy for silica-and multiple measures of herbivory by caterpillars of the generalist herbivore fall armyworm (Spodoptera frugiperda). RESULTS: Across all genetic subpopulations, low-latitude plants experienced less herbivory than high-latitude plants. Within genetic subpopulations, however, this relationship was inconsistent-the most widely distributed and phenotypically variable subpopulation (Atlantic) exhibited more consistent latitudinal trends than either of the other two subpopulations. The two physical resistance traits, LMA and leaf ash, were both highly heritable and positively associated with resistance to different measures of herbivory across all subpopulations, indicating their importance in defense against herbivores. Again, however, these relationships were inconsistent within subpopulations. CONCLUSIONS: Defensive gradients that occur across the entire species range may not arise within localized subpopulations. Thus, identifying the drivers of latitudinal gradients in herbivory defense may depend on adequately sampling the diversity within a species.


Assuntos
Herbivoria , Poaceae , Animais , Plantas , Genótipo , Folhas de Planta , Insetos
13.
Evol Anthropol ; 33(3): e22023, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38340074

RESUMO

Concerns about cuckoldry are a dominant theme in evolutionary studies of mating, frequently used to explain sex differences in reproductive strategies. However, studies in nonhuman species have shown that cuckoldry can be associated with important benefits. These insights have not been well integrated with the human literature, which continues to focus on anticuckoldry tactics and negative repercussions for men. I evaluate two key assumptions central to human models of cuckoldry: (1) men are being tricked into investing in nonbiological offspring and (2) investment in nonbiological offspring is wasted. The ethnographic data on fatherhood shows that the concepts of pater and genitor are complex and locally constructed ideas that often include explicit knowledge of extra-pair paternity, countering the idea that nonpaternity results from trickery. Furthermore, rather than being a "waste," paternity loss can be associated with important gains for men, helping to explain why men invest in nonbiological offspring.


Assuntos
Relações Extramatrimoniais , Paternidade , Feminino , Humanos , Masculino , Pai , Reprodução/fisiologia
14.
Cost Eff Resour Alloc ; 22(1): 1, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178078

RESUMO

BACKGROUND: Maternal and neonatal mortality in low- and middle-income countries is frequently caused by inadequate management of obstetric and neonatal complications and a shortage of skilled health workers. The availability of these workers is essential for effective and high-quality healthcare. To meet the needs of sexual, reproductive, maternal, new-born, child, and adolescent health by 2030, more than one million health workers, including 900 000 midwives, are required globally. Despite this, uncertainty persists regarding the return on investment in the health workforce. METHODS: The objective of this research was to determine the cost-benefit ratio of increasing investment in midwifery in Morocco from 2021 to 2030. A comparative analysis was conducted between scenarios "with" and "without" the additional investment. The costs and benefits were estimated using relevant data from national and international sources. RESULTS: Following the International Confederation of Midwives' recommendations, it is advised that Morocco recruit 760 midwives annually to achieve 95% of universal health coverage. This increase in midwifery could result in saving 120 593 lives by 2030, including reducing maternal deaths by 3 201, stillbirths by 48 399, and neonatal deaths by 68 993. The estimated economic benefit of investing in midwives was US$ 10 152 287 749, while the total cost was US$ 638 288 820. Consequently, the cost-benefit ratio was calculated as 15.91, indicating that investing in midwifery would provide 16 times more benefits than costs. CONCLUSION: Increasing investment in midwifery appears to be an efficient strategy for achieving comprehensive maternal and child health coverage in low- and middle-income countries.

15.
Cost Eff Resour Alloc ; 22(1): 51, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38880873

RESUMO

Alzheimer's disease (AD), breast cancer (BC) and prostate cancer (PC) continue to be high in the research and innovation agenda of the European Commission (EC). This is due to their exceptionally large burden to the national health systems, the profound economic effects of opportunity costs attributable to decreased working ability, premature mortality and the ever-increasing demand for both hospital and home-based medical care. Over the last two decades, the EC has been steadily increasing both the number of proposals being funded and the amounts of financial resources being allocated to these fields of research. This trend has continued throughout four consecutive science funding cycles, namely framework programme (FP)5, FP6, FP7 and Horizon 2020 (H2020). We performed a retrospective assessment of the outputs and outcomes of EC funding in AD, BC and PC research over the 1999-2019 period by means of selected indicators. These indicators were assessed for their ability to screen the past, present and future for an array of causal relationships and long-term trends in clinical, epidemiological and public health sphere, while considering also the broader socioeconomic impact of funded research on the society at large. This analysis shows that public-private partnerships with large industry and university-based consortia have led to some of the most impactful proposals being funded over the analysed time period. New pharmaceuticals, small molecules and monoclonal antibodies alike, along with screening and prevention, have been the most prominent sources of innovation in BC and PC, extending patients' survival and enhancing their quality of life. Unlike oncology, dementia drug development has been way less successful, with only minor improvements related to the quality of supportive medical care for symptoms and more sensitive diagnostics, without any ground-breaking disease-modifying treatment(s). Significant progresses in imaging diagnostics and nanotechnology have been largely driven by the participation of medical device industry multinational companies. Clinical trials funded by the EC were conducted, leading to the development of brand-new drug molecules featuring novel mechanisms of action. Some prominent cases of breakthrough discoveries serve as evidence for the European capability to generate cutting-edge technological innovation in biomedicine. Less productive areas of research may be reconsidered as priorities when shaping the new agenda for forthcoming science funding programmes.

16.
Philos Trans A Math Phys Eng Sci ; 382(2280): 20230401, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39183647

RESUMO

The UK's fusion energy approach has developed over the past 5 years to include government policy initiatives and a range of public sector investments designed to be delivered in partnership with the private sector. These have aimed to create an environment that stimulates innovation and investment to deliver economic as well as scientific and environmental benefits throughout the lifetime of the public sector fusion energy programme. The Spherical Tokamak for Energy Production acts as a focus and anchor for both public and private sector efforts to develop fusion energy, developing the supply chain and potential for Intellectual Property development and export opportunities well ahead of the anticipated STEP completion date of 2040. This is maximized by the UK's approach to a holistic research and innovation programme backed up by a regulatory and skills programme. This article is part of the theme issue 'Delivering Fusion Energy - The Spherical Tokamak for Energy Production (STEP)'.

17.
Health Econ ; 33(11): 2671-2684, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39175164

RESUMO

The health production function of the canonical health-capital model is generalized to allow the state of health to affect the total and marginal products of health investment. If the total and marginal products of health investment are nonincreasing functions of the state of health, then the solution of the generalized model is locally qualitatively identical to that of the canonical model. Moreover, and in contrast to the canonical model, the generalized model is able to rationalize the cycling of the state of health and health investment observed in some individuals. The necessary conditions on the health production function for cyclical behavior are identified as well.


Assuntos
Comportamentos Relacionados com a Saúde , Humanos , Nível de Saúde
18.
Health Econ ; 33(4): 714-747, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38155476

RESUMO

From an economic perspective, large investments in medical equipment are justifiable only when many patients benefit. Although rural hospitals play a crucial role locally, the treatments they can offer are limited. In this study, I characterize investment level that maximizes the total surplus, encompassing patients' welfare and producer surplus, and subtracting treatment costs. Specifically, I account for economic externalities generated by the investment in the rural hospital and for different utility losses that patients suffer when they cannot be treated locally. I demonstrate that the optimal investment level can be implemented if the Health Authority has the power to set specific prices for each disease. Additionally, I explore a decentralized situation wherein the investment decision lies with the rural hospital manager, and the Health Authority can only make a discrete decision between two payment systems: Fee-for-service, which covers all treatment costs, or Diagnosis-Related-Groups, which reimburses a price per patient based on the overall average cost. I find that the Diagnosis-Related-Groups system outperforms the Fee-for-service in terms of total surplus when the treatment cost at the rural hospital is lower. However, when the rural hospital has higher costs and the Health Authority seeks to incentivize investment, the Fee-for-service system is superior.


Assuntos
Hospitais Rurais , Investimentos em Saúde , Humanos , Custos de Cuidados de Saúde , Grupos Diagnósticos Relacionados , Planos de Pagamento por Serviço Prestado
19.
Environ Res ; 240(Pt 1): 117442, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37879394

RESUMO

Industrialized nations have witnessed a decline in environmental quality over the years. The potential of digitalization in mitigating environmental pollution is of significant interest. Drawing on firm-level data from listed Chinese companies between 2010 and 2020, including pollutant and financial metrics, this study investigates the influence of digitalization on industrial environmental pollution. We found that digitalization substantially diminishes the intensity of industrial pollution emissions. These findings hold even after employing instrumental variable tests, substituting the dependent variable with carbon dioxide emissions, and conducting a quasi-natural experiment in intelligent manufacturing. Moreover, our exploration of the underlying mechanisms reveals that the decline in pollution emission intensity attributable to digitalization stems from both structural and technological factors; specifically, it enhances environmental investment and fosters green innovation. The benefits of digitalization in curbing emission intensity are pronounced for firms characterized by lower pollution levels, executive leadership with environmental work backgrounds, heightened capital intensity, and elevated media coverage.


Assuntos
Poluentes Ambientais , Poluição Ambiental , China , Comércio , Desenvolvimento Econômico , Poluição Ambiental/prevenção & controle , Indústrias
20.
Environ Res ; 243: 117835, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38052358

RESUMO

In Greece, there is no organized practice in agricultural and animal wastes management. Their exploitation is still set aside, due mainly to economic reasons and lack of incentives for their efficient utilization. Therefore, in the present work a technoeconomic assessment for the environmentally friendly useful exploitation of biomass residues produced in the Prefectures of Ilia and Achaia (Western Greece) for the generation of energy by an integrated anaerobic digestion (AD)-pyrolysis processing plant was carried out. The processed biomass of the AD unit is corn residues and cattle manure, while the feedstock of pyrolysis unit is olive tree prunings. The residues will be transferred to collection areas by field tractors. Then an integrated harvester is used and afterwards, the residues are discharged from the lifting bin of the harvester to trucks and are transported to the processing unit. The total fixed capital for a capacity of 328,716 t/y is equal to 11.5 M€, while the initial working capital is equal to 2.1 M€. The total operational cost of this investment is estimated at 18.3 M€/y, the projected revenues amount to 21.4 M€/y and the net profit is equal to 3.1 M€/y. The return on investment is estimated at 23% and the payback period becomes equal to 4.4 years. From the sensitivity analysis becomes apparent that the capacity, the incentive cost, the fuel price, the products price and the total fixed capital affect significantly the investment characteristics of the proposed AD-pyrolysis processing unit. The amount of the expected profit is considered quite significant, and the evaluation criteria (return on investment and payback period) advocate for a more detailed examination of the investment plan, in the direction of undertaking the project.


Assuntos
Biocombustíveis , Pirólise , Animais , Bovinos , Biomassa , Anaerobiose , Esterco
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