This paper engages with recent work in political ecology that explores the ways in which scale is imbricated in environmental governance. Specifically, we analyze the deployment of specific ...ecological scales as putatively ‘natural’ governance units in rescaling processes. To undertake this analysis, the paper brings two sets of literature into dialogue: (1) political ecology of scale and (2) political economy of rescaling, drawing on theories of uneven development. Building on this literature, we develop the concept of an ecoscalar fix and explore its analytical potential through a case study of the rescaling of water governance in Alberta, Canada. We argue that although the ‘eco-scalar fix’ is usually framed as an apolitical governance change—particularly through the framing of particular scales (ie, the watershed) as ‘natural’—it is often, in fact, a deeply political move that reconfigures power structures and prioritizes some resource uses over others in ways that can entrench, rather than resolve, the crises it was designed to address. Moreover, we suggest that, although watershed governance is often discursively depicted as an environmental strategy (eg, internalizing environmental externalities by aligning decision making with ecological boundaries), it is often articulated with—and undertaken to address challenges that arise through—processes of uneven development.
Excavating sponges are among the most important macro-eroders of carbonate substrates in marine systems. Their capacity to remove substantial amounts of limestone makes these animals significant ...players that can unbalance the reef carbonate budget of tropical coral reefs. Nevertheless, excavating sponges are currently rarely incorporated in standardized surveys and experimental work is often restricted to a few species. Here were provide chemical and mechanical bioerosion rates for the six excavating sponge species most commonly found on the shallow reef of Curaçao (southern Caribbean): Cliona caribbaea, C. aprica, C. delitrix, C. amplicavata, Siphonodictyon brevitubulatum and Suberea flavolivescens. Chemical, mechanical and total bioerosion rates were estimated based on various experimental approaches applied to sponge infested limestone cores. Conventional standing incubation techniques were shown to strongly influence the chemical dissolution signal. Final rates, based on the change in alkalinity of the incubation water, declined significantly as a function of incubation time. This effect was mitigated by the use of a flow-through incubation system. Additionally, we found that mechanically removed carbonate fragments collected in the flow-through chamber (1 h) as well as a long-term collection method (1 wk) generally yielded comparable estimates for the capacity of these sponges to mechanically remove substratum. Observed interspecific variation could evidently be linked to the adopted boring strategy (i.e. gallery-forming, cavity-forming or network-working) and presence or absence of symbiotic zooxanthellae. Notably, a clear diurnal pattern was found only in species that harbour a dense photosymbiotic community. In these species chemical erosion was substantially higher during the day. Overall, the sum of individually acquired chemical and mechanical erosion using flow-through incubations was comparable to rates obtained gravimetrically. Such consistency is a first in this field of research. These findings support the much needed confirmation that, depending on the scientific demand, the different approaches presented here can be implemented concurrently as standardized methods.
Increased life expectancy is posing unprecedented challenges to healthcare systems worldwide. These include a sharp increase in the prevalence of chronic kidney disease (CKD) and of impaired ...nutritional status with malnutrition-protein-energy wasting (PEW) that portends worse clinical outcomes, including reduced survival. In older adults with CKD, a nutritional dilemma occurs when indications from geriatric nutritional guidelines to maintain the protein intake above 1.0 g/kg/day to prevent malnutrition need to be adapted to the indications from nephrology guidelines, to reduce protein intake in order to prevent or slow CKD progression and improve metabolic abnormalities. To address these issues, the European Society for Clinical Nutrition and Metabolism (ESPEN) and the European Renal Nutrition group of the European Renal Association (ERN-ERA) have prepared this conjoint critical review paper, whose objective is to summarize key concepts related to prevention and treatment of both CKD progression and impaired nutritional status using dietary approaches, and to provide guidance on how to define optimal protein and energy intake in older adults with differing severity of CKD. Overall, the authors support careful assessment to identify the most urgent clinical challenge and the consequent treatment priority. The presence of malnutrition-protein-energy wasting (PEW) suggests the need to avoid or postpone protein restriction, particularly in the presence of stable kidney function and considering the patient’s preferences and quality of life. CKD progression and advanced CKD stage support prioritization of protein restriction in the presence of a good nutritional status. Individual risk-benefit assessment and appropriate nutritional monitoring should guide the decision-making process. Higher awareness of the challenges of nutritional care in older adult patients with CKD is needed to improve care and outcomes. Research is advocated to support evidence-based recommendations, which we still lack for this increasingly large patient subgroup.
On the evenings of June 11 and 12, 2019, 5 and 6 days before full moon, broadcast spawning by four echinoderm species and two mollusc species was observed on the Marsa Shagra reef, Egypt (25° 14′ ...44.2" N, 34° 47′ 49.0" E). Water temperature was 28 °C and the invertebrates were observed at 2–8 m depth. The sightings included a single basket star
Astroboa nuda
(Lyman 1874), 2 large
Tectus dentatus
(Forskal 1775) sea snails, 14 individuals of the
Leiaster
cf.
leachi
(Gray 1840) sea star and 1
Mithrodia clavigera
(Lamarck 1816) sea star, 3
Pearsonothuria graeffei
(Semper 1868) sea cucumbers, and 2 giant clams,
Tridacna maxima
(Röding 1798). The observations presented here provide relevant information on broadcast spawning of non-coral invertebrate taxa in the Red Sea, where spawning is considerably less well documented than in other tropical geographical regions such as the Indo-Pacific and Caribbean.
Ocean acidification (OA) is expected to modify the structure and function of coral reef ecosystems by reducing calcification, increasing bioerosion, and altering the physiology of many marine ...organisms. Much of our understanding of these relationships is based on experiments with static OA treatments, although evidence suggests that the magnitude of diurnal fluctuations in carbonate chemistry may modulate the calcification response to OA. These light‐mediated swings in seawater pH are projected to become more extreme with OA, yet their impact on bioerosion remains unknown. We evaluated the influence of diurnal carbonate chemistry variability on the bioerosion rates of two Caribbean sponges: the zooxanthellate Cliona varians and azooxanthellate Cliothosa delitrix. Replicate fragments from multiple colonies of each species were exposed to four precisely controlled pH treatments: contemporary static (8.05 ± 0.00; mean pH ± diurnal pH oscillation), contemporary variable (8.05 ± 0.10), future OA static (7.80 ± 0.00), and future OA variable (7.80 ± 0.10). Significantly enhanced bioerosion rates, determined using buoyant weight measurements, were observed under more variable conditions in both the contemporary and future OA scenarios for C. varians, whereas the same effect was only apparent under contemporary pH conditions for C. delitrix. These results indicate that variable carbonate chemistry has a stimulating influence on sponge bioerosion, and we hypothesize that bioerosion rates evolve non‐linearly as a function of pCO2 resulting in different magnitudes and directions of rate enhancement/reduction between day and night, even with an equal fluctuation around the mean. This response appeared to be intensified by photosymbionts, evident by the consistently higher percent increase in bioerosion rates for photosynthetic C. varians across all treatments. These findings further suggest that more variable natural ecosystems may presently experience elevated sponge bioerosion rates and that the heightened impact of OA enhanced bioerosion on reef habitat could occur sooner than prior predictions.
We evaluated the influence of diurnal carbonate chemistry variability on the bioerosion rates of two Caribbean sponges: the zooxanthellate Cliona varians and azooxanthellate Cliothosa delitrix. We identified significantly enhanced bioerosion rates under more variable pH conditions in both contemporary (8.05 ± 0.10; mean pH ± diurnal pH oscillation) and future ocean acidification (7.80 ± 0.10) scenarios for C. varians, whereas the same effect was only apparent under contemporary pH conditions for C. delitrix. The findings indicate that variable pH conditions have a stimulating influence on sponge bioerosion and that more variable natural reef ecosystems may presently experience elevated sponge bioerosion rates.
Malignant mesothelioma (MMe) is a cancer with poor prognosis and resistance to standard treatments. Recent reports have highlighted the role of the
(
) in the development of MMe. In this study, the ...chemosensitivity of human mesothelioma cell lines carrying
wild-type (WT), mutant and silenced was analysed. The
mutant cells were significantly less sensitive than
WT cell lines to the clinically relevant drug gemcitabine. Silencing of
significantly increased resistance of MMe cells to gemcitabine. Cell cycle analysis suggested that gemcitabine induced Sub-G1 phase accumulation of the
WT cells and increased in the S-phase in both
WT and mutant cells. Analysis of the role of BAP1 in apoptosis suggested that gemcitabine induced early apoptosis in both
WT and
mutant cells but with a much higher degree in the WT cells. Effects on the population of cells in late apoptosis, which can mark necrosis and necroptosis, could not be seen in the mutant cells, highlighting the possibility that BAP1 plays a role in several types of cell death. Significantly decreased DNA damage in the form of double-strand breaks was observed in gemcitabine-treated
mutant cells, compared to
WT cells under the same conditions. After
silencing, a significant decrease in DNA damage in the form of double-strand breaks was observed compared to cells transfected with scramble siRNA. Taken together, the results presented in this manuscript shed light on the role of BAP1 in the response of MMe cells to gemcitabine treatment and in particular in the control of the DNA damage response, therefore providing a potential route for more efficient MMe therapy.
A common assumption is that human chromosomes carry equal chances of mis-segregation during compromised cell division. Human chromosomes vary in multiple parameters that might generate bias, but ...technological limitations have precluded a comprehensive analysis of chromosome-specific aneuploidy. Here, by imaging specific centromeres coupled with high-throughput single-cell analysis as well as single-cell sequencing, we show that aneuploidy occurs non-randomly following common treatments to elevate chromosome mis-segregation. Temporary spindle disruption leads to elevated mis-segregation and aneuploidy of a subset of chromosomes, particularly affecting chromosomes 1 and 2. Unexpectedly, we find that a period of mitotic delay weakens centromeric cohesion and promotes chromosome mis-segregation and that chromosomes 1 and 2 are particularly prone to suffer cohesion fatigue. Our findings demonstrate that inherent properties of individual chromosomes can bias chromosome mis-segregation and aneuploidy rates, with implications for studies on aneuploidy in human disease.
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•Aneuploidy rates vary between chromosomes after drug-induced mis-segregation•Chromosomes 1 and 2 comprise a large proportion of anaphase lagging chromosomes•Mitotic delay and cohesion fatigue drive chromosome mis-segregation•Chromosomes 1 and 2 are particularly prone to cohesion fatigue
Worrall et al. show that individual human chromosomes can respond differently to defects in mitosis that lead to chromosome mis-segregation. Following nocodazole washout, chromosomes 1 and 2 are particularly prone to a weakening of centromeric cohesion and elevated rates of chromosome lagging during anaphase.
An altered intestinal microbiota composition has been implicated in the pathogenesis of metabolic disease including obesity and type 2 diabetes mellitus (T2DM). Low grade inflammation, potentially ...initiated by the intestinal microbiota, has been suggested to be a driving force in the development of insulin resistance in obesity. Here, we report that bacterial DNA is present in mesenteric adipose tissue of obese but otherwise healthy human subjects. Pyrosequencing of bacterial 16S rRNA genes revealed that DNA from the Gram-negative species Ralstonia was most prevalent. Interestingly, fecal abundance of Ralstonia pickettii was increased in obese subjects with pre-diabetes and T2DM. To assess if R. pickettii was causally involved in development of obesity and T2DM, we performed a proof-of-concept study in diet-induced obese (DIO) mice. Compared to vehicle-treated control mice, R. pickettii-treated DIO mice had reduced glucose tolerance. In addition, circulating levels of endotoxin were increased in R. pickettii-treated mice. In conclusion, this study suggests that intestinal Ralstonia is increased in obese human subjects with T2DM and reciprocally worsens glucose tolerance in DIO mice.
A major driver of cancer chromosomal instability is replication stress, the slowing or stalling of DNA replication. How replication stress and genomic instability are connected is not known. ...Aphidicolin-induced replication stress induces breakages at common fragile sites, but the exact causes of fragility are debated, and acute genomic consequences of replication stress are not fully explored.
We characterize DNA copy number alterations (CNAs) in single, diploid non-transformed cells, caused by one cell cycle in the presence of either aphidicolin or hydroxyurea. Multiple types of CNAs are generated, associated with different genomic regions and features, and observed copy number landscapes are distinct between aphidicolin and hydroxyurea-induced replication stress. Coupling cell type-specific analysis of CNAs to gene expression and single-cell replication timing analyses pinpointed the causative large genes of the most recurrent chromosome-scale CNAs in aphidicolin. These are clustered on chromosome 7 in RPE1 epithelial cells but chromosome 1 in BJ fibroblasts. Chromosome arm level CNAs also generate acentric lagging chromatin and micronuclei containing these chromosomes.
Chromosomal instability driven by replication stress occurs via focal CNAs and chromosome arm scale changes, with the latter confined to a very small subset of chromosome regions, potentially heavily skewing cancer genome evolution. Different inducers of replication stress lead to distinctive CNA landscapes providing the opportunity to derive copy number signatures of specific replication stress mechanisms. Single-cell CNA analysis thus reveals the impact of replication stress on the genome, providing insights into the molecular mechanisms which fuel chromosomal instability in cancer.
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