resilience aggregation
Dotaz
Zobrazit nápovědu
BACKGROUND: The regional disparity of heatwave-related mortality over a long period has not been sufficiently assessed across the globe, impeding the localisation of adaptation planning and risk management towards climate change. We quantified the global mortality burden associated with heatwaves at a spatial resolution of 0.5°×0.5° and the temporal change from 1990 to 2019. METHODS AND FINDINGS: We collected data on daily deaths and temperature from 750 locations of 43 countries or regions, and 5 meta-predictors in 0.5°×0.5° resolution across the world. Heatwaves were defined as location-specific daily mean temperature ≥95th percentiles of year-round temperature range with duration ≥2 days. We first estimated the location-specific heatwave-mortality association. Secondly, a multivariate meta-regression was fitted between location-specific associations and 5 meta-predictors, which was in the third stage used with grid cell-specific meta-predictors to predict grid cell-specific association. Heatwave-related excess deaths were calculated for each grid and aggregated. During 1990 to 2019, 0.94% (95% CI: 0.68-1.19) of deaths [i.e., 153,078 cases (95% eCI: 109,950-194,227)] per warm season were estimated to be from heatwaves, accounting for 236 (95% eCI: 170-300) deaths per 10 million residents. The ratio between heatwave-related excess deaths and all premature deaths per warm season remained relatively unchanged over the 30 years, while the number of heatwave-related excess deaths per 10 million residents per warm season declined by 7.2% per decade in comparison to the 30-year average. Locations with the highest heatwave-related death ratio and rate were in Southern and Eastern Europe or areas had polar and alpine climates, and/or their residents had high incomes. The temporal change of heatwave-related mortality burden showed geographic disparities, such that locations with tropical climate or low incomes were observed with the greatest decline. The main limitation of this study was the lack of data from certain regions, e.g., Arabian Peninsula and South Asia. CONCLUSIONS: Heatwaves were associated with substantial mortality burden that varied spatiotemporally over the globe in the past 30 years. The findings indicate the potential benefit of governmental actions to enhance health sector adaptation and resilience, accounting for inequalities across communities.
- MeSH
- celosvětové zdraví trendy MeSH
- extrémní horko * škodlivé účinky MeSH
- klimatické změny * MeSH
- lidé MeSH
- mortalita trendy MeSH
- roční období MeSH
- vysoká teplota škodlivé účinky MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Freshwaters are increasingly exposed to complex mixtures of pharmaceutical and personal care products (PPCPs) from municipal wastewater, which are known to alter freshwater communities' structure and functioning. However, their interaction with other disturbances and whether their combined effects can impact ecological resilience (i.e., the ability of a system to tolerate disturbances without altering the system's original structure and processes) remain unexplored. Using in situ mesocosms in 2 lakes with different nutrient levels (mesotrophic and eutrophic), we assessed whether a pulse exposure to sublethal concentrations of 12 PPCPs affects the ecological resilience of natural phytoplankton communities that experienced an abrupt environmental change involving the destabilization of the water column through mixing. Such mixing events are predicted to increase as the effects of climate change unfold, leading to more frequent storms, which disrupt stratification in lakes and force communities to restructure. We assessed their combined effects on community metrics (biomass, species richness, and composition) and their relative resilience using 4 indicators (cross-scale, within-scale, aggregation length, and gap length), inferred from phytoplankton communities by discontinuity analysis. The mixing disturbance alone had negligible effects on the community metrics, but when combined with chemical contaminants significant changes were measured: reducing total biomass, species richness, and altered community composition of phytoplankton. Once these changes occurred, they persisted until the end of the experiment (day 20), when the communities' structures from the 2 highest exposure levels diverged from the controls. The resilience indicators were not affected by PPCPs but differed significantly between lakes, with lower resilience found in the eutrophic lake. Thus, PPCPs can significantly alter community structures and reinforce mechanisms that maintain ecosystems in a "degraded state." Environ Toxicol Chem 2019;38:2197-2208. © 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.
- MeSH
- biodiverzita MeSH
- biomasa MeSH
- chemické látky znečišťující vodu toxicita MeSH
- fylogeneze MeSH
- fytoplankton účinky léků MeSH
- jezera chemie MeSH
- voda chemie MeSH
- výrobky pro domácnost toxicita MeSH
- vystavení vlivu životního prostředí * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The survival of spirochetes from the Borrelia burgdorferi (sensu lato) complex in a hostile environment is achieved by the regulation of differential gene expression in response to changes in temperature, salts, nutrient content, acidity fluctuation, multiple host or vector dependent factors, and leads to the formation of dormant subpopulations of cells. From the other side, alterations in the level of gene expression in response to antibiotic pressure leads to the establishment of a persisters subpopulation. Both subpopulations represent the cells in different physiological states. "Dormancy" and "persistence" do share some similarities, e.g. both represent cells with low metabolic activity that can exist for extended periods without replication, both constitute populations with different gene expression profiles and both differ significantly from replicating forms of spirochetes. Persisters are elusive, present in low numbers, morphologically heterogeneous, multi-drug-tolerant cells that can change with the environment. The definition of "persisters" substituted the originally-used term "survivors", referring to the small bacterial population of Staphylococcus that survived killing by penicillin. The phenomenon of persisters is present in almost all bacterial species; however, the reasons why Borrelia persisters form are poorly understood. Persisters can adopt varying sizes and shapes, changing from well-known forms to altered morphologies. They are capable of forming round bodies, L-form bacteria, microcolonies or biofilms-like aggregates, which remarkably change the response of Borrelia to hostile environments. Persisters remain viable despite aggressive antibiotic challenge and are able to reversibly convert into motile forms in a favorable growth environment. Persisters are present in significant numbers in biofilms, which has led to the explanation of biofilm tolerance to antibiotics. Considering that biofilms are associated with numerous chronic diseases through their resilient presence in the human body, it is not surprising that interest in persisting cells has consequently accelerated. Certain diseases caused by pathogenic bacteria (e.g. tuberculosis, syphilis or leprosy) are commonly chronic in nature and often recur despite antibiotic treatment. Three decades of basic and clinical research have not yet provided a definite answer to the question: is there a connection between persisting spirochetes and recurrence of Lyme disease in patients?
Biofilm matrix forms a dynamic microenvironment facilitating the resilience of the biofilm. Extracellular DNA (eDNA) is one of the matrix components playing a crucial role in the cell adhesion, aggregation and structure stabilization. Its sticky nature and negative charge reduce the penetration of antimicrobials and further enable the biofilm tolerance or even resistance. The resistance can be encoded in the biofilm matrix genetic information. Moreover, the biofilm matrix with eDNA creates an ideal environment for gene transfer. For all above mentioned reasons, eDNA is a substance with a significant potential for the biofilm disruption in food processing, as well as in medicine. The combination of several different techniques successful in biofilm disruption could facilitate even eradication of the biofilm with various pathogens.
- Klíčová slova
- narušení biofilmu,
- MeSH
- bakteriální léková rezistence MeSH
- biofilmy * účinky léků MeSH
- DNA bakterií MeSH
- extracelulární matrix MeSH
- rekombinace genetická MeSH
- Publikační typ
- práce podpořená grantem MeSH
BACKGROUND AND AIMS: The gut microbiome, an aggregate genome of trillions of microorganisms residing in the human gastrointestinal tract, is now known to play a critical role in human health and predisposition to disease. It is also involved in the biotransformation of xenobiotics and several recent studies have shown that the gut microbiota can affect the pharmacokinetics of orally taken drugs with implications for their oral bioavailability. METHODS: Review of Pubmed, Web of Science and Science Direct databases for the years 1957-2016. RESULTS AND CONCLUSIONS: Recent studies make it clear that the human gut microbiota can play a major role in the metabolism of xenobiotics and, the stability and oral bioavailability of drugs. Over the past 50 years, more than 30 drugs have been identified as a substrate for intestinal bacteria. Questions concerning the impact of the gut microbiota on drug metabolism, remain unanswered or only partially answered, namely (i) what are the molecular mechanisms and which bacterial species are involved? (ii) What is the impact of host genotype and environmental factors on the composition and function of the gut microbiota, (iii) To what extent is the composition of the intestinal microbiome stable, transmissible, and resilient to perturbation? (iv) Has past exposure to a given drug any impact on future microbial response, and, if so, for how long? Answering such questions should be an integral part of pharmaceutical research and personalised health care.
- MeSH
- acetylace MeSH
- Bacteria metabolismus MeSH
- biologická dostupnost MeSH
- hydrolýza MeSH
- léčivé přípravky chemie metabolismus MeSH
- lidé MeSH
- oxidace-redukce MeSH
- střevní mikroflóra fyziologie MeSH
- systém (enzymů) cytochromů P-450 metabolismus MeSH
- xenobiotika metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Rockström et al. (2009a, 2009b) have warned that humanity must reduce anthropogenic impacts defined by nine planetary boundaries if "unacceptable global change" is to be avoided. Chemical pollution was identified as one of those boundaries for which continued impacts could erode the resilience of ecosystems and humanity. The central concept of the planetary boundary (or boundaries) for chemical pollution (PBCP or PBCPs) is that the Earth has a finite assimilative capacity for chemical pollution, which includes persistent, as well as readily degradable chemicals released at local to regional scales, which in aggregate threaten ecosystem and human viability. The PBCP allows humanity to explicitly address the increasingly global aspects of chemical pollution throughout a chemical's life cycle and the need for a global response of internationally coordinated control measures. We submit that sufficient evidence shows stresses on ecosystem and human health at local to global scales, suggesting that conditions are transgressing the safe operating space delimited by a PBCP. As such, current local to global pollution control measures are insufficient. However, while the PBCP is an important conceptual step forward, at this point single or multiple PBCPs are challenging to operationalize due to the extremely large number of commercial chemicals or mixtures of chemicals that cause myriad adverse effects to innumerable species and ecosystems, and the complex linkages between emissions, environmental concentrations, exposures and adverse effects. As well, the normative nature of a PBCP presents challenges of negotiating pollution limits amongst societal groups with differing viewpoints. Thus, a combination of approaches is recommended as follows: develop indicators of chemical pollution, for both control and response variables, that will aid in quantifying a PBCP(s) and gauging progress towards reducing chemical pollution; develop new technologies and technical and social approaches to mitigate global chemical pollution that emphasize a preventative approach; coordinate pollution control and sustainability efforts; and facilitate implementation of multiple (and potentially decentralized) control efforts involving scientists, civil society, government, non-governmental organizations and international bodies.
V současné době je resilience chápána jako osobnostní vlastnost, souhrn vlastností/faktorů, výsledek adaptace či proces. Většina odborníků a také velká část výzkumu resilience vychází z prvních tří pojetí, které ale představují spíše zkoumání "resilientnosti" jedince než samotné resilience. Až zkoumání procesů, probíhajících např. při vzájemné interakci mezi rizikovými vlivy, faktory resilience, důsledky (projevy osobnosti, chováním, přítomností problémů atd.) a dalšími proměnnými umožňuje poznat a pochopit resilienci (skutečnou podstatu toho, jak resilience probíhá). Jinak řečeno, výzkum interakcí mezi rysovými faktory (např. self-esteem), vztahovými faktory (např. vztahové sítě), riziky a důsledky je důležitý pro pochopení toho JAK a KDY resilience působí.
The nature and definition of resilience, despite the extensive 40 years of research, is still unclear. Currently is resilience seen as a personality trait, sum of the traits/factors, result of adaptation, or as a process. The concept of resilience as personality traits is usually tied to uni-dimensional or "simplex" theories of resistance as Hardiness, Sense of Control, Ego-Resiliency, Self-efficacy, Sense of Coherence, or specific personality traits. Multidimensional concepts see resilience as a complex of personality and social (environmental) factors that work in interaction, complement or replace each other, and, in aggregate, create a comprehensive picture of resilience. The concept of resilience as the result of adaptation examines resilience in terms of the presence/absence of adverse/pathological manifestations, consequences and outcomes in relation to the earlier effect of stressful, risky or otherwise unfavorable situations. Finally, the concept of resilience as the process examines individual's response to risk factors or wounds that are present in the environment. Resilience is thus a process consisting of interactions between individual characteristics and the environment. Most experts and a large part of resilience research is based on the first three concepts that however explore how "resilient" the individual is rather than resilience itself, since they are based on "diagnosing" or at best dimensional, at worse dichotomous rating of the individual's resilience (within personality trait approach), or on the evaluation of the presence/absence of factors/source of resilience, thereby they are still holding the "diagnostic" approach (within multidimensional approach). Only the examination of processes, such as the ongoing interaction between these risk factors, resilience factors, outcomes (expressions of personality, behavior, presence of problems, etc.) and other variables allows us to understand resilience (the true nature of how resilience takes place). In other words, research on interactions between trait factors (e.g. self-esteem), relational factors (e.g. relationship networks), the risks and outcomes is important for understanding HOW and WHEN resilience acts.
- MeSH
- lidé MeSH
- osobnost MeSH
- psychická odolnost * MeSH
- psychologická teorie * MeSH
- rozvoj osobnosti MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- MeSH
- centrální nervový systém fyziologie patofyziologie patologie MeSH
- diagnostické zobrazování metody využití MeSH
- exekutivní funkce fyziologie MeSH
- kardiovaskulární nemoci prevence a kontrola MeSH
- kognitivní dysfunkce patologie prevence a kontrola MeSH
- lidé MeSH
- neurodegenerativní nemoci etiologie prevence a kontrola MeSH
- patologické stavy, příznaky a symptomy * MeSH
- poruchy paměti patologie prevence a kontrola MeSH
- pozornost fyziologie MeSH
- proteinové agregáty fyziologie genetika MeSH
- psychická odolnost MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- stárnutí * fyziologie patologie MeSH
- statistika jako téma MeSH
- Check Tag
- lidé MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Publikační typ
- práce podpořená grantem MeSH
Cyanobacteria pose a serious threat to water resources around the world. This is compounded by the fact that they are extremely resilient, having evolved numerous protective mechanisms to ensure their dominant position in their ecosystem. We show that treatment with nanoparticles of zerovalent iron (nZVI) is an effective and environmentally benign method for destroying and preventing the formation of cyanobacterial water blooms. The nanoparticles have multiple modes of action, including the removal of bioavailable phosphorus, the destruction of cyanobacterial cells, and the immobilization of microcystins, preventing their release into the water column. Ecotoxicological experiments showed that nZVI is a highly selective agent, having an EC(50) of 50 mg/L against cyanobacteria; this is 20-100 times lower than its EC(50) for algae, daphnids, water plants, and fishes. The primary product of nZVI treatment is nontoxic and highly aggregated Fe(OH)(3), which promotes flocculation and gradual settling of the decomposed cyanobacterial biomass.
- MeSH
- Araceae účinky léků růst a vývoj MeSH
- čištění vody metody MeSH
- Daphnia účinky léků fyziologie MeSH
- hořčice rodu Sinapis účinky léků růst a vývoj MeSH
- kořeny rostlin účinky léků růst a vývoj MeSH
- kovové nanočástice toxicita MeSH
- látky znečišťující vodu analýza MeSH
- listy rostlin účinky léků růst a vývoj MeSH
- Microcystis účinky léků růst a vývoj MeSH
- mikrobiologie vody MeSH
- mikrocystiny analýza MeSH
- Scenedesmus účinky léků růst a vývoj MeSH
- železo toxicita MeSH
- živorodka MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
