Read by QxMD icon Read

Ecological systems theory

Zhen-Hua Guan, Chang-Yong Ma, Han-Lan Fei, Bei Huang, Wen-He Ning, Qing-Yong Ni, Xue-Long Jiang, Peng-Fei Fan
Gibbons in China represent the northernmost margin of present day gibbon species distribution (around N25°). Compared to tropical habitats, northern gibbon habitats are characterized by low temperatures and remarkable seasonal variation in fruit abundance. How gibbons adapt to their cold and seasonal habitats and what ecological factors affect their sociality are key questions for understanding their ecology and social system evolution, the elucidation of which will contribute to the conservation of these special populations/species...
March 12, 2018: Zoological Research
Guoqi Li, Lei Deng, Gaoxi Xiao, Pei Tang, Changyun Wen, Wuhua Hu, Jing Pei, Luping Shi, H Eugene Stanley
Complex networks characterize the nature of internal/external interactions in real-world systems including social, economic, biological, ecological, and technological networks. Two issues keep as obstacles to fulfilling control of large-scale networks: structural controllability which describes the ability to guide a dynamical system from any initial state to any desired final state in finite time, with a suitable choice of inputs; and optimal control, which is a typical control approach to minimize the cost for driving the network to a predefined state with a given number of control inputs...
March 15, 2018: Scientific Reports
Stephanie M Topp, Chanda Mwamba, Anjali Sharma, Njekwa Mukamba, Laura K Beres, Elvin Geng, Charles B Holmes, Izukanji Sikazwe
BACKGROUND: Failure to keep people living with HIV engaged in life-long care and treatment has serious implications for individual and population-level health. Nested within a four-province study of HIV care and treatment outcomes, we explored the dynamic role of social and service-related factors influencing retention in HIV care in Zambia. METHODS: From a stratified random sample of 31 facilities, eight clinics were selected, one urban and one rural from each province...
2018: PloS One
Robert Stephen Cantrell, Chris Cosner, Xiao Yu
Most classical models for the movement of organisms assume that all individuals have the same patterns and rates of movement (for example, diffusion with a fixed diffusion coefficient) but there is empirical evidence that movement rates and patterns may vary among different individuals. A simple way to capture variation in dispersal that has been suggested in the ecological literature is to allow individuals to switch between two distinct dispersal modes. We study models for populations whose members can switch between two different nonzero rates of diffusion and whose local population dynamics are subject to density dependence of logistic type...
December 2018: Journal of Biological Dynamics
Kristin A Dalope, Leonard J Woods
Family dynamics are increasingly being influenced by digital media. Three frameworks are described to help clinicians to understand and respond to this influence. First, a social-ecological framework shows how media has both a direct and indirect impact on individuals, relationships, communities, and society. Next, family systems theory is introduced to demonstrate digital media-related interactions within families. Finally, a developmental framework explores the role of digital media in shaping parenting. These theories are then integrated into practical strategies that clinicians can use, including recommendations and resources from the American Academy of Pediatrics...
April 2018: Child and Adolescent Psychiatric Clinics of North America
W C Chuang, A Garmestani, T N Eason, T L Spanbauer, H B Fried-Petersen, C P Roberts, S M Sundstrom, J L Burnett, D G Angeler, B C Chaffin, L Gunderson, D Twidwell, C R Allen
Scholars from many different intellectual disciplines have attempted to measure, estimate, or quantify resilience. However, there is growing concern that lack of clarity on the operationalization of the concept will limit its application. In this paper, we discuss the theory, research development and quantitative approaches in ecological and community resilience. Upon noting the lack of methods that quantify the complexities of the linked human and natural aspects of community resilience, we identify several promising approaches within the ecological resilience tradition that may be useful in filling these gaps...
March 1, 2018: Journal of Environmental Management
K K Davison, N Kitos, A Aftosmes-Tobio, T Ash, A Agaronov, M Sepulveda, J Haines
Despite recognition that parents are critical stakeholders in childhood obesity prevention, obesity research has overwhelmingly focused on mothers. In a recent review, fathers represented only 17% of parent participants in >600 observational studies on parenting and childhood obesity. The current study examined the representation of fathers in family interventions to prevent childhood obesity and characteristics of interventions that include fathers compared with those that only include mothers. Eligible studies included family-based interventions for childhood obesity prevention published between 2008 and 2015 identified in a recent systematic review...
February 28, 2018: Preventive Medicine
Yazhuo Deng, David R Paul
PURPOSE: This study drew upon the ecological system theory to demonstrate rural-urban differences in the relationships between the availability of recreational facilities, physical activity (PA), functional health status, and depressive symptoms in middle-aged and older Chinese adults. METHODS: Nationally representative data (n = 5949) from the Chinese Health and Retirement Longitudinal Study (CHARLS, 2011-2013) were examined using the multigroup structural equation modeling approach...
March 1, 2018: International Journal of Behavioral Medicine
Paul F Cook, Sarah J Schmiege, Blaine Reeder, Sara Horton-Deutsch, Nancy K Lowe, Paula Meek
BACKGROUND: Health promotion and chronic disease management both require behavior change, but people find it hard to change behavior despite having good intentions. The problem arises because patients' narratives about experiences and intentions are filtered through memory and language. These narratives inaccurately reflect intuitive decision-making or actual behaviors. OBJECTIVES: We propose a principle-temporal immediacy-as a moderator variable that explains which of two mental systems (narrative or intuitive) will be activated in any given situation...
March 2018: Nursing Research
Stephanie W Cawthon, Bentley Fink, Sarah Schoffstall, Erica Wendel
Social skills are a vehicle by which individuals negotiate important relationships. The present article presents historical data on how social skills in deaf students were conceptualized and studied empirically during the period 1990-2015. Using a structured literature review approach, the researchers coded 266 articles for theoretical frameworks used and constructs studied. The vast majority of articles did not explicitly align with a specific theoretical framework. Of the 37 that did, most focused on socioemotional and cognitive frameworks, while a minority drew from frameworks focusing on attitudes, developmental theories, or ecological systems theory...
2018: American Annals of the Deaf
Callie Chappell, Tadashi Fukami
The species of yeasts that colonize floral nectar can modify the mutualistic relationships between plants and pollinators by changing the chemical properties of nectar. Recent evidence supporting this possibility has led to increased interest among ecologists in studying these fungi as well as the bacteria that interact with them in nectar. Although not fully explored, nectar yeasts also constitute a promising natural microcosm that can be used to facilitate development of general ecological theory. We discuss the methodological and conceptual advantages of using nectar yeasts from this perspective, including simplicity of communities, tractability of dispersal, replicability of community assembly, and the ease with which the mechanisms of species interactions can be studied in complementary experiments conducted in the field and the laboratory...
February 24, 2018: Yeast
Sophie Pask, Cathryn Pinto, Katherine Bristowe, Liesbeth van Vliet, Caroline Nicholson, Catherine J Evans, Rob George, Katharine Bailey, Joanna M Davies, Ping Guo, Barbara A Daveson, Irene J Higginson, Fliss Em Murtagh
BACKGROUND: Palliative care patients are often described as complex but evidence on complexity is limited. We need to understand complexity, including at individual patient-level, to define specialist palliative care, characterise palliative care populations and meaningfully compare interventions/outcomes. AIM: To explore palliative care stakeholders' views on what makes a patient more or less complex and insights on capturing complexity at patient-level. DESIGN: In-depth qualitative interviews, analysed using Framework analysis...
February 1, 2018: Palliative Medicine
Aditya R Nayak, Malcolm N McFarland, James M Sullivan, Michael S Twardowski
In situ measurements were undertaken to characterize particle fields in undisturbed oceanic environments. Simultaneous, co-located depth profiles of particle fields and flow characteristics were recorded using a submersible holographic imaging system and an acoustic Doppler velocimeter, under different flow conditions and varying particle concentration loads, typical of those found in coastal oceans and lakes. Nearly one million particles with major axis lengths ranging from ∼14 μm to 11.6 mm, representing diverse shapes, sizes, and aspect ratios were characterized as part of this study...
January 2018: Limnology and Oceanography
David G Angeler, Craig R Allen, Maj-Liz Persson
BACKGROUND: The term resilience describes stress-response patterns of subjects across scientific disciplines. In ecology, advances have been made to clearly distinguish resilience definitions based on underlying mechanistic assumptions. Engineering resilience (rebound) is used for describing the ability of subjects to recover from adverse conditions (disturbances), and is the rate of recovery. In contrast, the ecological resilience definition considers a systemic change: when complex systems (including humans) respond to disturbances by reorganizing into a new regime (stable state) where structural and functional aspects have fundamentally changed relative to the prior regime...
February 9, 2018: International Journal of Bipolar Disorders
Devin Kirk, Natalie Jones, Stephanie Peacock, Jessica Phillips, Péter K Molnár, Martin Krkošek, Pepijn Luijckx
The complexity of host-parasite interactions makes it difficult to predict how host-parasite systems will respond to climate change. In particular, host and parasite traits such as survival and virulence may have distinct temperature dependencies that must be integrated into models of disease dynamics. Using experimental data from Daphnia magna and a microsporidian parasite, we fitted a mechanistic model of the within-host parasite population dynamics. Model parameters comprising host aging and mortality, as well as parasite growth, virulence, and equilibrium abundance, were specified by relationships arising from the metabolic theory of ecology...
February 7, 2018: PLoS Biology
Masayuki Ushio, Chih-Hao Hsieh, Reiji Masuda, Ethan R Deyle, Hao Ye, Chun-Wei Chang, George Sugihara, Michio Kondoh
Ecological theory suggests that large-scale patterns such as community stability can be influenced by changes in interspecific interactions that arise from the behavioural and/or physiological responses of individual species varying over time. Although this theory has experimental support, evidence from natural ecosystems is lacking owing to the challenges of tracking rapid changes in interspecific interactions (known to occur on timescales much shorter than a generation time) and then identifying the effect of such changes on large-scale community dynamics...
February 7, 2018: Nature
Ashley M Reaney, Mónica Saldarriaga-Córdoba, Daniel Pincheira-Donoso
BACKGROUND: Life diversifies via adaptive radiation when natural selection drives the evolution of ecologically distinct species mediated by their access to novel niche space, or via non-adaptive radiation when new species diversify while retaining ancestral niches. However, while cases of adaptive radiation are widely documented, examples of non-adaptively radiating lineages remain rarely observed. A prolific cold-climate lizard radiation from South America (Phymaturus), sister to a hyper-diverse adaptive radiation (Liolaemus), has extensively diversified phylogenetically and geographically, but with exceptionally minimal ecological and life-history diversification...
February 6, 2018: BMC Evolutionary Biology
Fabien Génin, Judith C Masters
OBJECTIVE: The socioecological model (SEM) is a popular collection of controversial models purporting to explain mating systems in terms of ecological and social parameters. Despite its guise of objectivity, several of its hypotheses assume Victorian gender stereotypes of active, competing males heedlessly sowing their seeds, and cautious, passive females, imprisoned by greater costs of reproduction and their consequent resourceߚdependence. METHODS: We enter this debate by taking a previously neglected explanatory approach borrowed from species theory...
January 2018: American Journal of Physical Anthropology
Daniel S Maynard, Carlos A Serván, Stefano Allesina
Ecological networks that exhibit stable dynamics should theoretically persist longer than those that fluctuate wildly. Thus, network structures which are over-represented in natural systems are often hypothesised to be either a cause or consequence of ecological stability. Rarely considered, however, is that these network structures can also be by-products of the processes that determine how new species attempt to join the community. Using a simulation approach in tandem with key results from random matrix theory, we illustrate how historical assembly mechanisms alter the structure of ecological networks...
January 29, 2018: Ecology Letters
Masaru Hasegawa, Emi Arai
The effect of sexual selection on extinction risk remains unclear. In theory, sexual selection can lead to both increase and decrease extinction probability depending on the ecology of the study system. Thus, combining different groups might obscure patterns that can be found in groups that share similar ecological features. Using phylogenetic comparative analysis, we studied sexual plumage dimorphism in relation to the perceived risk of extinction in hirundines (subfamily: Hirundininae), in which all species are socially monogamous aerial foragers...
January 2018: Ecology and Evolution
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"