Ecological systems theory

Excessive discharge of nitrogen-containing chemical products into the natural water environment leads to the serious environmental problem of nitrate-nitrogen pollution, threatening the ecological balance and human health. In this study, we propose an efficient denitrification electrochemical method utilizing iron-doped zeolite imidazolium framework derived defective nitrogen-doped carbon (d-FeNC) catalysts. The d-FeNC catalyst exhibited 97 % nitrate removal efficiency and 94 % total nitrogen (TN) removal, and the reaction rate constant was increased from 0...

Dispersal evolution modifies diverse spatial processes, such as range expansions or biological invasions of single species, but we are currently lacking a realistic vision for metacommunities. Focusing on antagonistic species interactions, we review existing theory of dispersal evolution between natural enemies, and explain how this might be relevant for classic themes in host-parasite evolutionary ecology, namely virulence evolution or local adaptation. Specifically, we highlight the importance of considering the simultaneous (co)evolution of dispersal and interaction traits...

Solid waste is increasing rapidly worldwide. In this study, the solid waste (household waste, construction and demolition waste and industrial waste) management systems are treated as reverse supply chain to analyze the critical operational issues based on complex adaptive system theory. At the single-layer, the complexity of the various nodes at a layer arises from rational decision-making and behavioral heterogeneity. The solid waste generation layer is employed as an example to investigate the complexity of node behavioral decisions...

Youth and young adults (YYA) with intellectual and developmental disabilities (IDD) have high rates of co-occurring mental health (MH) conditions. The time during transition from pediatric to adult health and mental health care can be a very challenging, with risk of loss of services leading to poor outcomes. This study aimed to explore barriers to transition from pediatric to adult health and mental health care and services for individuals with IDD and co-occurring MH conditions, by eliciting the view of stakeholders, including disability advocates...

Species-area relationships (SAR) constitute a key aspect of ecological theory and are integral to other scientific disciplines, such as biogeography, which have played a crucial role in advancing biology. The theory of insular biogeography provides a clear example. This theory initially expanded from true islands to other types of systems characterized by their insularity. One such approach was linked to geoedaphic islands, as seen in gypsum outcrops. While these continental areas have been considered insular systems, only limited and mostly indirect evidence thereof has been provided...

Understanding the evolution of coral endosymbiosis requires a predictive framework that integrates life-history theory and ecology with cell biology. The time has come to bridge disciplines and use a model systems approach to achieve this aim.

Recently, the Fenton-like reaction using peroxymonosulfate (PMS) has been acknowledged as a potential method for breaking down organic pollutants. In this study, we successfully synthesized a highly efficient and stable single atom molybdenum (Mo) catalyst dispersed on nitrogen-doped carbon (Mo-NC-0.1). This catalyst was then utilized for the first time to activate PMS and degrade bisphenol A (BPA). The Mo-NC-0.1/PMS system demonstrated the ability to completely degrade BPA within just 20 min. Scavenging tests and density functional theory (DFT) calculations have demonstrated that the primary reactive oxygen species was singlet oxygen (1 O2 ) produced by Mo-N4 sites...

OBJECTIVE: Previous research has shown a correlation between family adaptability and adolescent depression. However, there is a lack of studies that have investigated the underlying mechanism between family adaptability and adolescent depression. Based on the Ecological Systems Theory, this study aims to investigate the link between family adaptability and depression in adolescents, mediated by the sequential roles of social support and self-efficacy. METHODS: The sample consisted of 1086 students randomly selected from seven public middle schools in Shandong Province, Eastern China...

Climate change threatens the lives and livelihoods of smallholder farmers throughout the global South. In order to address the challenges these farmers face, researchers and practitioners need reasonable theoretical models of how humans and the environment interact within social-ecological systems (SES). Social-ecological resilience theory has proved to be a popular model for understanding human environment relationships within SES; however, the theory lacks a sophisticated understanding of power, relying instead on outdated functionalist sociological approaches...

In 2050, most areas of biodiversity significance will be heavily influenced by multiple drivers of environmental change. This includes overlap with the introduced ranges of many alien species that negatively impact biodiversity. With the decline in biodiversity and increase in all forms of global change, the need to envision the desired qualities of natural systems in the Anthropocene is growing, as is the need to actively maintain their natural values. Here, we draw on community ecology and invasion biology to (i) better understand trajectories of change in communities with a mix of native and alien populations, and (ii) to frame approaches to the stewardship of these mixed-species communities...

According to the cognitive model of suicide, interactions between hopelessness and attentional biases toward suicidal information create a narrowed attentional focus on suicide as a viable solution, particularly in the presence of life stress, leading to increased suicide risk. This study used a dynamic systems approach to examine the short-term temporal patterns between stress, hopelessness, suicide-specific rumination, and suicidal intent. Adults (N = 237; M = 27.12 years; 62% cisgender women; 87% White/European American) with elevated suicidal ideation completed ecological momentary assessments six times a day for 14 days...

INTRODUCTION: Income inequality, a pivotal determinant of general and mental health, operates through intricate mechanisms at various geographical scales. While established at country or region levels, the impact of lower-level (municipal or neighborhood) inequality remains inconsistent. This study explores the influence of regional- and municipal-level income inequality on individual psychological distress during the COVID-19 pandemic in Italy, employing a multilevel data analysis. MATERIALS AND METHODS: In a post hoc analysis of data from the first wave of the pandemic (March to April 2020), three hierarchical levels were considered: individual participants, municipalities, and regions...

IMPORTANCE: Dynamical systems theory is widely used to explain tipping points, cycles, and chaos in complex systems ranging from the climate to ecosystems. It has been suggested that the same theory may be used to explain the nature and dynamics of psychiatric disorders, which may come and go with symptoms changing over a lifetime. Here we review evidence for the practical applicability of this theory and its quantitative tools in psychiatry. OBSERVATIONS: Emerging results suggest that time series of mood and behavior may be used to monitor the resilience of patients using the same generic dynamical indicators that are now employed globally to monitor the risks of collapse of complex systems, such as tropical rainforest and tipping elements of the climate system...

IMPORTANCE: Psychiatric disorders may come and go with symptoms changing over a lifetime. This suggests the need for a paradigm shift in diagnosis and treatment. Here we present a fresh look inspired by dynamical systems theory. This theory is used widely to explain tipping points, cycles, and chaos in complex systems ranging from the climate to ecosystems. OBSERVATIONS: In the dynamical systems view, we propose the healthy state has a basin of attraction representing its resilience, while disorders are alternative attractors in which the system can become trapped...

Children with disabilities need comprehensive intervention spanning health, education, and social systems from infancy through adulthood, with ongoing assessment of outcomes. While assistive technology is crucial, it must be complemented by inclusive learning options and other systemic interventions. Bronfenbrenner's Ecological Systems Theory guides this approach. A project in South Africa's Northern Cape Province utilized Acumen's Lean Data methodology for monitoring and evaluation. This methodology emphasizes rapid, technology-enabled data collection to inform stakeholders effectively...

Large mammalian herbivores substantially impact ecosystem functioning. As their populations are dramatically altered globally, disentangling their consumptive and non-consumptive effects is critical to advance mechanistic understanding and improve prediction of effects over ecosystem and Earth-system spatial extents. Mathematical models have played an important role in clarifying potential mechanisms of herbivore zoogeochemistry, based mostly on their consumptive effects as primary consumers and recyclers of organic and inorganic matter via defecation and urination...

The evolution processes of complex systems carry key information in the systems' functional properties. Applying machine learning algorithms, we demonstrate that the historical formation process of various networked complex systems can be extracted, including protein-protein interaction, ecology, and social network systems. The recovered evolution process has demonstrations of immense scientific values, such as interpreting the evolution of protein-protein interaction network, facilitating structure prediction, and particularly revealing the key co-evolution features of network structures such as preferential attachment, community structure, local clustering, degree-degree correlation that could not be explained collectively by previous theories...

The objective of this paper is to integrate Urban Political Ecology (UPE) as a theory for identifying under-exposed urban dimensions of Antimicrobial Resistance (AMR). A UPE lens allows us to conceptualize urbanization as a ubiquitous socio-ecological process and an interpretive frame that could inform AMR governance strategies across related contexts by: a) situating AMR risks in relation to urbanization processes shaping social and political co-determinants of such systemic threats as climate change; b) aligning UPE scholarship with One Health (OH) approaches that address AMR to reveal the under-exposed link of AMR to environmental threats and broader structural dimensions that influence these threats; and c) identifying shared AMR and environmental governance pathways that inform the rationale for more equitable governance arrangements...

Polyculture practices are important for achieving sustainable aquaculture development. Recently, hard clams polyculture in intensive shrimp ponds has been encouraged because bivalves can consume excess nutrients in aquaculture systems and sequester carbon. To evaluate the bioremediation potential of hard clams polyculture in intensive shrimp ponds, this study built an assessment model based on individual growth models and estimated the potential for nitrogen and phosphorus removal as well as CO2 fixation by hard clams...

Ahmed Kathrada (1929-2017), an anti-apartheid activist, political prisoner, and parliamentary politician had been at the centre of South Africa's liberation struggle for six decades and is remembered as a soft-spoken, strong-willed and incorruptible freedom fighter. This psychobiography uses the career development framework of Jeffrey Greenhaus and the ecological human development systems framework proposed by Urie Bronfenbrenner to investigate and illuminate Kathrada's life history. Kathrada was purposively selected as subject due to his extraordinary contributions to the liberation struggle...