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1.
Proc Natl Acad Sci U S A ; 121(36): e2313191121, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39196625

RESUMO

Achieving more sustainable adaptation to social-environmental change demands the transformation of the narratives that provide the rationale for risk governance. These narratives often reflect long-standing beliefs about social and political relationships, ascribe actions and responsibilities, and specify solutions to risk. When such solutions are implemented through material investments in landscapes, these narratives become embedded in physical infrastructure with long legacies. Dominant narratives can mask a range of divergent problem framings. By masking alternatives, narratives can contribute to the persistence of unsustainable governance trajectories. Decision-support tools have begun to represent narratives as drivers of system dynamics; making narratives visible can reveal opportunities for more sustainable governance. We present the results of the project "The Dynamics of Multi-Scalar Adaptation in the Megalopolis", a dynamic, exploratory model of socio-hydrological risks in Mexico City that was designed to both endogenize and simultaneously challenge the dominant narratives that characterize water-risk governance in the city. Qualitative data characterize dominant narratives at city and borough scales. An agent-based model, informed by multicriteria decision analysis and coupled with hydrological, urbanization, and climatic model inputs, permitted the development of exploratory governance scenarios designed to challenge dominant narratives. Scenarios revealed how dominant narratives may contribute to the persistence of vulnerability "hotspots" in the city, despite stated goals of equity and vulnerability alleviation. Participatory workshops with representatives of the city government illustrate how making such narratives visible through exploratory modeling can lead to a questioning of prior assumptions and causal relations, recognition of a need for intersectoral collaboration, and insights into potential management strategies.

3.
Proc Natl Acad Sci U S A ; 116(12): 5277-5284, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30111542

RESUMO

Maintaining safe operating spaces for exploited natural systems in the face of uncertainty is a key sustainability challenge. This challenge can be viewed as a problem in which human society must navigate in a limited space of acceptable futures in which humans enjoy sufficient well-being and avoid crossing planetary boundaries. A critical obstacle is the nature of society as a controller with endogenous dynamics affected by knowledge, values, and decision-making fallacies. We outline an approach for analyzing the role of knowledge infrastructure in maintaining safe operating spaces. Using a classic natural resource problem as an illustration, we find that a small safe operating space exists that is insensitive to the type of policy implementation, while in general, a larger safe operating space exists which is dependent on the implementation of the "right" policy. Our analysis suggests the importance of considering societal response dynamics to varying policy instruments in defining the shape of safe operating spaces.


Assuntos
Conservação dos Recursos Naturais/legislação & jurisprudência , Ecossistema , Desenvolvimento Sustentável/legislação & jurisprudência , Tomada de Decisões , Humanos , Conhecimento , Incerteza
4.
Comput Econ ; 59(1): 1-25, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33162678

RESUMO

The extent to which employees change jobs, known as the job mobility rate, has been steadily declining in the US for decades. This decline is understood to have a negative impact on both productivity and wages, and econometric studies fail to support any single cause brought forward. This decline coincides with decreases in household savings, increases in household debt and wage stagnation. We propose that the decline could be the consequence of a complex interaction between mobility, savings, wages and debt, such that if changing jobs incurs costs which are paid out of savings, or incurs debt in the absence of sufficient savings, a negative feedback loop is generated. People are further restricted in making moves by their debt obligations and inability to save, which in turn depresses wages further. To explore this hypothesis, we developed a stylized model in which agents chose their employment situation based on their opportunities and preferences for work and where there are costs to changing jobs and the possibility of borrowing to meet those costs. We indeed found evidence of a negative feedback loop involving changes, wages, savings and debt, as well as evidence that this dynamic results in a level of wealth inequality on the same scale as we see today in the US.

5.
Proc Natl Acad Sci U S A ; 114(5): 921-925, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28096383

RESUMO

Smallholder agricultural systems, strongly dependent on water resources and investments in shared infrastructure, make a significant contribution to food security in developing countries. These communities are being increasingly integrated into the global economy and are exposed to new global climate-related risks that may affect their willingness to cooperate in community-level collective action problems. We performed field experiments on public goods with private and collective risks in 118 small-scale rice-producing communities in four countries. Our results indicate that increasing the integration of those communities with the broader economic system is associated with lower investments in public goods when facing collective risks. These findings indicate that local public good provision may be negatively affected by collective risks, especially in communities more integrated with the market economy.


Assuntos
Agricultura , Participação da Comunidade , Abastecimento de Alimentos , Adulto , China , Mudança Climática , Colômbia , Humanos , Nepal , Oryza , Risco , Tailândia
7.
Environ Model Softw ; 134: 104873, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32958993

RESUMO

Being able to replicate research results is the hallmark of science. Replication of research findings using computational models should, in principle, be possible. In this manuscript, we assess code sharing and model documentation practices of 7500 publications about individual-based and agent-based models. The code availability increased over the years, up to 18% in 2018. Model documentation does not include all the elements that could improve the transparency of the models, such as mathematical equations, flow charts, and pseudocode. We find that articles with equations and flow charts being cited more among other model papers, probably because the model documentation is more transparent. The practices of code sharing improve slowly over time, partly due to the emergence of more public repositories and archives, and code availability requirements by journals and sponsors. However, a significant change in norms and habits need to happen before computational modeling becomes a reproducible science.

8.
J Environ Manage ; 241: 407-417, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31030122

RESUMO

Urban adaptation to climate change is likely to emerge from the responses of residents, authorities, and infrastructure providers to the impact of flooding, water scarcity, and other climate-related hazards. These responses are, in part, modulated by political relationships under cultural norms that dominate the institutional and collective decisions of public and private actors. The legacy of these decisions, which are often associated with investment in hard and soft infrastructure, has lasting consequences that influence current and future vulnerabilities. Making those decisions visible, and tractable is, therefore, an urgent research and political challenge in vulnerability assessments. In this work, we present a modeling framework to explore scenarios of institutional decision-making and socio-political processes and the resultant effects on spatial patterns of vulnerability. The approach entails using multi-criteria decision analysis, agent-based models, and geographic information simulation. The approach allows for the exploration of uncertainties, spatial patterns, thresholds, and the sensitivities of vulnerability outcomes to different policy scenarios. Here, we present the operationalization of the framework through an intentionally simplified model example of the governance of water in Mexico City. We discuss results from this example as part of a larger effort to empirically implement the framework to explore sociohydrological risk patterns and trade-offs of vulnerability in real urban landscapes.


Assuntos
Mudança Climática , Inundações , Cidades , Tomada de Decisões , México
9.
J Environ Manage ; 227: 200-208, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30193209

RESUMO

Residents of Mexico City experience major hydrological risks, including flooding events and insufficient potable water access for many households. A participatory modeling project, MEGADAPT, examines hydrological risk as co-constructed by both biophysical and social factors and aims to explore alternative scenarios of governance. Within the model, neighborhoods are represented as agents that take actions to reduce their sensitivity to exposure and risk. These risk management actions (to protect their households against flooding and scarcity) are based upon insights derived from focus group discussions within various neighborhoods. We developed a role-playing game based on the model's rules in order to validate the assumptions we made about residents' decision-making given that we had translated qualitative information from focus group sessions into a quantitative model algorithm. This enables us to qualitatively validate the perspective and experience of residents in an agent-based model mid-way through the modeling process. Within the context of described hydrological events and the causes of these events, residents took on the role of themselves in the game and were asked to make decisions about how to protect their households against scarcity and flooding. After the game, we facilitated a discussion with residents about whether or not the game was realistic and how it could be improved. The game helped to validate our assumptions, validate the model with community members, and reinforced our connection with the community. We then discuss the potential further development of the game as a learning and communication tool.


Assuntos
Inundações , Hidrologia , Gestão de Riscos , Tomada de Decisões , México
10.
Evol Anthropol ; 24(2): 62-72, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25914360

RESUMO

Paleoanthropologists (scientists studying human origins) universally recognize the evolutionary significance of ancient climates and environments for understanding human origins. Even those scientists working in recent phases of human evolution, when modern humans evolved, agree that hunter-gatherer adaptations are tied to the way that climate and environment shape the food and technological resource base. The result is a long tradition of paleoanthropologists engaging with climate and environmental scientists in an effort to understand if and how hominin bio-behavioral evolution responded to climate and environmental change. Despite this unusual consonance, the anticipated rewards of this synergy are unrealized and, in our opinion, will not reach potential until there are some fundamental changes in the way the research model is constructed. Discovering the relation between climate and environmental change to human origins must be grounded in a theoretical framework and a causal understanding of the connection between climate, environment, resource patterning, behavior, and morphology, then move beyond the strict correlative research that continues to dominate the field.


Assuntos
Evolução Biológica , Clima , Paleontologia/métodos , Projetos de Pesquisa , Animais , Meio Ambiente , Humanos , Modelos Teóricos
12.
Proc Natl Acad Sci U S A ; 108(35): 14620-5, 2011 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-21873245

RESUMO

Hypoxia has been shown to be an important microenvironmental parameter influencing tumor progression and treatment efficacy. Patient guidance for hypoxia-targeted therapy requires evaluation of tumor oxygenation, preferably in a noninvasive manner. The aim of this study was to evaluate and validate the uptake of [(18)F]HX4, a novel developed hypoxia marker for PET imaging. A heterogeneous accumulation of [(18)F]HX4 was found within rat rhabdomyosarcoma tumors that was significantly (P < 0.0001) higher compared with the surrounding tissues, with temporal increasing tumor-to-blood ratios reaching a plateau of 7.638 ± 0.926 and optimal imaging properties 4 h after injection. [(18)F]HX4 retention in normal tissues was found to be short-lived, homogeneous and characterized by a fast progressive temporal clearance. Heterogeneity in [(18)F]HX4 tumor uptake was analyzed based on 16 regions within the tumor according to the different orthogonal planes at the largest diameter. Validation of heterogeneous [(18)F]HX4 tumor uptake was shown by a strong and significant relationship (r = 0.722; P < 0.0001) with the hypoxic fraction as calculated by the percentage pimonidazole-positive pixels. Furthermore, a causal relationship with tumor oxygenation was established, because combination treatment of nicotinamide and carbogen resulted in a 40% reduction (P < 0.001) in [(18)F]HX4 tumor accumulation whereas treatment with 7% oxygen breathing resulted in a 30% increased uptake (P < 0.05). [(18)F]HX4 is therefore a promising candidate for noninvasive detection and evaluation of tumor hypoxia at a macroscopic level.


Assuntos
Hipóxia Celular , Radioisótopos de Flúor , Imidazóis , Neoplasias Experimentais/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Triazóis , Animais , Biomarcadores , Masculino , Nitroimidazóis/farmacologia , Ratos
13.
PLoS One ; 19(8): e0308363, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39102405

RESUMO

There is limited research about how groups solve collective action problems in uncertain environments, especially if groups are confronted with unknown unknowns. We aim to develop a more comprehensive view of the characteristics that allow both groups and individuals to navigate such issues more effectively. In this article, we present the results of a new online experiment where individuals make decisions of whether to contribute to the group or pursue self-interest in an environment with high uncertainty, including unknown unknowns. The behavioral game, Port of Mars is framed as a first-generation habitat on Mars where participants have to make decisions on how much to invest in the shared infrastructure to maintain system health and how much to invest in personal goals. Participants can chat during the game, and take surveys before and after the game in order to measure personality attributes and observations from the game. Initial results suggest that a higher average social value orientation and more communication are the key factors that explain why some groups are more successful than others in surviving Port of Mars. Neither other attributes of players nor the group's communication content explain the observed differences between groups.


Assuntos
Marte , Humanos , Masculino , Feminino , Adulto , Adulto Jovem , Tomada de Decisões , Jogos Experimentais , Comunicação , Incerteza , Comportamento Cooperativo , Adolescente
14.
PLoS One ; 19(8): e0307832, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39178192

RESUMO

Rule enforcement is critical in democratic, self-governing societies. Many political disputes occur when citizens do not understand the fundamental rationales for enforcement (e.g., COVID-19 pandemic). We examined how naïve groups learn and develop wise enforcement systems. Based on theories from behavioral economics, political science, psychology, and education, we predicted that groups need to experience failure of an enforcement system, but be guided on restorative justice principles to collectively learn from this failure. Undergraduate students (N = 288) from a Midwestern U.S. metropolitan university self-governed a simulated common-pool resource with real financial payoffs. Groups began with one of three conditions designed to create different experiences with enforcement and regulatory failure: (a) no enforcement (no communication or peer sanctioning), (b) lax enforcement (communication with peer-sanctioning), or (c) regulatory abuse (peer sanctioning without communication). Half then received facilitated guidance on restorative justice principles (e.g., discuss whether/why to use sanctions). To examine cooperation, we measured how well participants maintained the resource. To examine group learning, we created a novel coding system, which tracked groups' constitutional decisions about conservation agreements and enforcement, conceptual understanding, and the enforcement systems they created. The no-enforcement and lax-enforcement conditions quickly yielded moderate cooperation via voluntary agreements. However, such agreements prevented groups from discovering how and why to use enforcement (peer sanctioning) to improve performance. Initial exposure to regulatory failure had different effects depending on facilitation. Unfacilitated groups fixated on initial misconceptions, causing them to abandon or create less sophisticated enforcement systems, hindering cooperation. Facilitated groups learned from prior failure-discovering principles of wise enforcement (e.g., collective efficiency, self-restraint)-and created more sophisticated enforcement systems (e.g., coordinated sanctions) that improved cooperation. Guidance on restorative justice principles and experience with regulatory abuse may be necessary preconditions for naïve individuals to understand and develop wiser collective enforcement systems.


Assuntos
COVID-19 , Justiça Social , Humanos , Masculino , Feminino , COVID-19/epidemiologia , COVID-19/prevenção & controle , Adulto Jovem , Aplicação da Lei , Estudantes/psicologia , SARS-CoV-2 , Adulto , Aprendizagem , Universidades
15.
Int J Occup Saf Ergon ; 30(2): 450-459, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38378446

RESUMO

Objectives. It is prescribed to determine blue-light hazard (BLH) weighted radiances, LB, for an assessment of spotlights with an angular subtense α≥11mrad. The BLH weighted irradiance, EB, can be used alternatively for smaller sources. Appropriate instruments are not common among persons commissioned with risk assessment (RA), and especially LB measurements may be challenging. Therefore, a practical BLH RA approach is proposed that is based on illuminance, Ev, pre-calculated blackbody BLH efficacies of luminous radiation, KB,vPlanck, and solid angle considerations. Methods. The practicality of this method was examined and compared against other RA approaches. Results. To ensure comparability of the applied instruments, measurements were performed close to a radiance standard, showing deviations within the lamp's expanded uncertainties (<4%), whereas the deviations were ±15% for longer distances. Focusing on a complex light-emitting diode (LED) spotlight, all detected values could be converted to LB by means of the RA methods within ±20%. Two field tests with several spotlights yielded maximum permissible exposure durations (MPED) obtained from the different RA approaches that agreed among each other within uncertainties largely below ±30%. Conclusion. The general practicality of the proposed Ev method can be concluded for a workplace BLH RA of white-light sources.


Assuntos
Luz , Iluminação , Exposição Ocupacional , Local de Trabalho , Medição de Risco/métodos , Humanos , Exposição Ocupacional/análise
17.
PLoS One ; 17(5): e0268019, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35507605

RESUMO

It is puzzling how altruistic punishment of defectors can evolve in large groups of nonrelatives, since punishers should voluntarily bear individual costs of punishing to benefit those who do not pay the costs. Although two distinct mechanisms have been proposed to explain the puzzle, namely voluntary participation and group-level competition and selection, insights into their joint effects have been less clear. Here we investigated what could be combined effects of these two mechanisms on the evolution of altruistic punishment and how these effects can vary with nonparticipants' individual payoff and group size. We modelled altruistic punishers as those who contribute to a public good and impose a fine on each defector, i.e., they are neither pure punishers nor excluders. Our simulation results show that voluntary participation has negative effects on the evolution of cooperation in small groups regardless of nonparticipants' payoffs, while in large groups it has positive effects within only a limited range of nonparticipants' payoff. We discuss that such asymmetric effects could be explained by evolutionary forces emerging from voluntary participation. Lastly, we suggest that insights from social science disciplines studying the exit option could enrich voluntary participation models.


Assuntos
Teoria dos Jogos , Punição , Altruísmo , Evolução Biológica , Comportamento Cooperativo , Processos Grupais
18.
BMJ Health Care Inform ; 29(1)2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35922094

RESUMO

OBJECTIVES: To investigate the impact on efficiency and quality of preprostatectomy multidisciplinary therapy conferences (MDT) at Karolinska University Hospital related to the use of a digital solution compared with standard of care. Further, to explore whether gains in MDT efficiency and quality impact oncological or functional patient outcomes. METHODS: We conducted a prospective, observational study of preoperative prostate cancer MDT at Karolinska between February 2017 and March 2021, including 1329 patients. We compared efficiency and quality of the standard MDT and the MDT using the digital solution IntelliSpace Precision Medicine Multidisciplinary Team Orchestrator (ISPM) based on the previously used MDT-MODe approach. Clinical and patient-reported functional outcomes were derived from the medical records and the Swedish National Prostate Cancer Register. RESULTS: While ISPM was used during the MDT meeting, the time spent per patient was reduced by 24% (p<0.001) and most of the MDT-MODe items were scored significantly higher. There was a reduction in pelvic lymph-node dissection procedures in the ISPM cohort (p=0.001) and an increased proportion of unilateral nerve-sparing procedures (p=0.005), while all other outcome-related measures were not significantly different between the two patient groups. DISCUSSION AND CONCLUSION: To increase the value of the MDT, all data relevant for treatment decision need to be purposefully presented and compiled, which also enables secondary use of the data.The use of a digital solution during preoperative MDTs for prostate cancer decision making at Karolinska University Hospital improved the efficiency and quality of this multidisciplinary team meeting without impacting patient outcomes.


Assuntos
Equipe de Assistência ao Paciente , Neoplasias da Próstata , Tomada de Decisões , Humanos , Masculino , Estudos Prospectivos , Neoplasias da Próstata/terapia
19.
Eur J Nucl Med Mol Imaging ; 37(9): 1663-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20369236

RESUMO

BACKGROUND AND PURPOSE: Noninvasive PET imaging of tumour hypoxia could help in the selection of those patients who could benefit from chemotherapy or radiation with specific antihypoxic treatments such as bioreductive drugs or hypoxic radiosensitizers. In this phase I trial, we aimed to determine the toxicity of [(18)F]HX4, a member of the 2-nitroimidazole family, at different dose levels. The secondary aim was to analyse image quality related to the HX4 dose and the timing of imaging. METHODS: Patients with a histologically proven solid cancer without curative treatment options were eligible for this study. A study design with two dose steps was used in which a single dose of a maximum of 222 MBq (step 1) or 444 MBq (step 2) [(18)F]HX4 was injected. Toxicity was scored on day 0 and on days 3 and 7 after injection, according to the CTCAE 3.0 scoring system. PET/CT images of the largest tumour site were acquired 30, 60 and 120 min after injection. RESULTS: Six patients with stage IV carcinoma were included, four with non-small-cell lung carcinoma, one with thymus carcinoma, and one with colon carcinoma. No toxicity was observed in any of the patients at either dose level. The median tumour to muscle ratio 120 min after injection was 1.40 (range 0.63-1.98). CONCLUSION: The findings of this study showed that [(18)F]HX4 PET imaging for the detection of hypoxia is not associated with any toxicity. Imaging was successful; however, future trials are needed to determine the optimal image parameters.


Assuntos
Nitroimidazóis/efeitos adversos , Tomografia por Emissão de Pósitrons , Triazóis/efeitos adversos , Idoso , Hipóxia Celular , Relação Dose-Resposta a Droga , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Nitroimidazóis/administração & dosagem , Fatores de Tempo , Triazóis/administração & dosagem
20.
Sci Rep ; 10(1): 4136, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-32139800

RESUMO

Tipping point dynamics are fundamental drivers for sustainable transition pathways of social-ecological systems (SES). Current research predominantly analyzes how crossing tipping points causes regime shifts, however, the analysis of potential transition pathways from these social and ecological tipping points is often overlooked. In this paper, we analyze transition pathways and the potential outcomes that these may lead to via a stylized model of a system composed of interacting agents exploiting resources and, by extension, the overall ecosystem. Interactions between the social and the ecological system are based on a perception-exploitation framework. We show that the presence of tipping points in SES may yield counter-intuitive social-ecological transition pathways. For example, the high perception of an alarming ecological state among agents can provide short-term ecological benefits, but can be less effective in the long term, compared to a low-perception condition. This work also highlights how understanding non-linear interactions is critical for defining suitable transition pathways of any SES.

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