Global warming is predicted to increase both average temperatures and the frequency and duration of heat waves. Tropical ectotherms, particularly those living in warm environments are more prone to ...receive heat impacts. Then, it is crucial to identify those populations already exposed to high temperatures that may be at risk of decimation by ongoing warming. We assessed heating risk in a population of the fish species Astyanax bimaculatus, inhabiting hot pools in intermittent streams in the Brazilian Caatinga ecoregion. We experimentally examined the upper thermal tolerance (CTmax), and provided estimates of warming tolerance (WT), as the difference between CTmax and micro‐environmental peak temperatures (Tmax). Two CTmax estimates ranged between 37.6 and 40.6°C, whereas pond Tmax ranged between 34.6 and 41.3°C. This determines very narrow, even negative WTs, for these extreme heated A. bimaculatus populations, which ultimately may determine their local extinction in the coming decades.
in Portuguese is available with online material.
Prevê‐se que o aquecimento global aumente tanto as temperaturas médias como a frequência e duração das ondas de calor. Ectotérmicos tropicais, principalmente aqueles que habitam ambientes temperados, estão mais expostos a impactos térmicos. Portanto, identificar populações que já estão expostas a temperaturas altas o suficiente para serem ameaçadas pelo aquecimento atual é crucial. O risco de exposição a altas temperaturas foi estabelecido na espécie de peixe Astyanax bimaculatus, que habita poças quentes nos rios intermitentes presentes na ecorregião conhecida como Caatinga. A tolerância térmica superior (CTmax) foi aferida experimentalmente e apresentamos medidas de tolerância térmica (WT), definida como a diferença entre a CTmax e as temperaturas máximas registradas na escala microambiental (Tmax). Duas estimativas de CTmax ficaram entre 37,6°C e 40,6°C, enquanto o Tmax das poças variou entre 34,6°C e 41,3°C. Isso determina valores muito estreitos, e até mesmo negativos, de WTs para a população de A. bimaculatus estudada, o que pode vir a determinar sua extinção em décadas futuras.
The objective of the present study is to analyze and compare the cutting performance of segmented diamond blades when dry-cutting concrete. A cutting criteria is proposed to characterize the wear of ...the blades by measuring the variation of the external diameter and the weight loss of the blade. The results exhibit the cutting blade SB-A, which has twice the density of diamonds and large contact area, exhibits less wear even though the material removal rate is higher compared with the other two cutting blades. Additionally, the surface topography of the different blades is evaluated to examine the impact of wear depending on the surface profile and the distribution of the diamonds in the blade's matrix. Large number of diamonds pull-out are found in blades type SB-C, which additionally shows the worst wear resistant capability. As a conclusion, the cutting efficiency of the blade is found to be related to the density of embedded diamonds and the type of the surface profile of the cutting blade after reaching the stop criteria.
Background
Systemic lupus erythematosus is a heterogeneous chronic inflammatory autoimmune disorder characterized by an exacerbated expression of cytokines and chemokines in different tissues and ...organs. Renal involvement is a significant contributor to the morbidity and mortality of systemic lupus erythematosus, and its diagnosis is based on renal biopsy, an invasive procedure with a high risk of complications. Therefore, the development of alternative, non-invasive diagnostic tests for kidney disease in patients with systemic lupus erythematosus is a priority.
Aim
To evaluate the plasma levels of a panel of cytokines and chemokines using multiplex xMAP technology in a cohort of Colombian patients with active and inactive systemic lupus erythematosus, and to evaluate their potential as biomarkers of renal involvement.
Results
Plasma from 40 systemic lupus erythematosus non-nephritis patients and 80 lupus nephritis patients with different levels of renal involvement were analyzed for 39 cytokines using Luminex xMAP technology. Lupus nephritis patients had significantly increased plasma eotaxin, TNF-α, interleukin-17-α, interleukin-10, and interleukin-15 as compared to the systemic lupus erythematosus non-nephritis group. Macrophage-derived chemokine, growth regulated oncogene alpha, and epidermal growth factor were significantly elevated in systemic lupus erythematosus non-nephritis patients when compared to lupus nephritis individuals. Plasma eotaxin levels allowed a discrimination between systemic lupus erythematosus non-nephritis and lupus nephritis patients, for which we performed a receiver operating characteristic curve to confirm. We observed a correlation of eotaxin levels with active nephritis (Systemic Lupus Erythematosus Disease Activity Index). Our data indicate that circulating cytokines and chemokines could be considered good predictors of renal involvement in individuals with systemic lupus erythematosus.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Tranexamic acid can prevent death due to bleeding after trauma and post-partum haemorrhage. We aimed to assess whether tranexamic acid reduces haematoma expansion and improves outcome in adults with ...stroke due to intracerebral haemorrhage.
We did an international, randomised placebo-controlled trial in adults with intracerebral haemorrhage from acute stroke units at 124 hospital sites in 12 countries. Participants were randomly assigned (1:1) to receive 1 g intravenous tranexamic acid bolus followed by an 8 h infusion of 1 g tranexamic acid or a matching placebo, within 8 h of symptom onset. Randomisation was done centrally in real time via a secure website, with stratification by country and minimisation on key prognostic factors. Treatment allocation was concealed from patients, outcome assessors, and all other health-care workers involved in the trial. The primary outcome was functional status at day 90, measured by shift in the modified Rankin Scale, using ordinal logistic regression with adjustment for stratification and minimisation criteria. All analyses were done on an intention-to-treat basis. This trial is registered with the ISRCTN registry, number ISRCTN93732214.
We recruited 2325 participants between March 1, 2013, and Sept 30, 2017. 1161 patients received tranexamic acid and 1164 received placebo; the treatment groups were well balanced at baseline. The primary outcome was assessed for 2307 (99%) participants. The primary outcome, functional status at day 90, did not differ significantly between the groups (adjusted odds ratio aOR 0·88, 95% CI 0·76–1·03, p=0·11). Although there were fewer deaths by day 7 in the tranexamic acid group (101 9% deaths in the tranexamic acid group vs 123 11% deaths in the placebo group; aOR 0·73, 0·53–0·99, p=0·0406), there was no difference in case fatality at 90 days (250 22% vs 249 21%; adjusted hazard ratio 0·92, 95% CI 0·77–1·10, p=0·37). Fewer patients had serious adverse events after tranexamic acid than after placebo by days 2 (379 33% patients vs 417 36% patients), 7 (456 39% vs 497 43%), and 90 (521 45% vs 556 48%).
Functional status 90 days after intracerebral haemorrhage did not differ significantly between patients who received tranexamic acid and those who received placebo, despite a reduction in early deaths and serious adverse events. Larger randomised trials are needed to confirm or refute a clinically significant treatment effect.
National Institute of Health Research Health Technology Assessment Programme and Swiss Heart Foundation.
•Active Living Walls (ALW) cool, bio-filter and humidify indoor air.•In ALW plants grow directly on a vertical surface through which an air flow is forced.•Drops in temperature between 0.8 and 4.8°C ...were observed during ALW operation.•The cooling process is more efficient under drier and warmer initial air conditions.•Saturation efficiency (η) of the system ranged within the interval 0.36–0.46.
Living walls are systems that allow the development of vegetation in a vertical surface attached to building facades or indoor walls. Traditionally, they have behaved as ‘passive’ bio-filters, but new approaches and technologies are moving towards their integration within the building's air conditioning and ventilation systems. In an Active Living Wall (ALW), air is forced to pass through the vegetated wall to take advantage of their evaporative cooling potential as well as the capacity of these biological systems to purify air. In the case of indoor ALWs, air is cooled, bio-filtered and humidified thus potentially reducing ventilation requirements. This work describes a prototypic indoor ALWs installed at the University of Seville (Spain). Preliminary results of its performance on indoor air conditions (temperature and humidity) are presented and discussed. Drops in temperature between 0.8 and 4.8°C have been observed at different distances from the ALW. The cooling process was more efficient when the initial conditions of the room were drier and warmer.
Aim
To investigate the effects of liver fibrosis (LF) on the pro‐inflammatory mediators and periapical bone resorption of apical periodontitis (AP) in rats.
Methodology
Forty male Wistar rats were ...distributed into four groups: C – control, AP – rats with AP, LF – rats with LF, AP + LF – rats with AP and LF. LF was induced by carbon tetrachloride administration for 8 weeks and surgical bile duct ligation for 4 weeks; AP was induced in the teeth of rats by dental pulp exposure to the oral environment for 30 days. Jaws and livers were removed after euthanasia. Haematoxylin and Eosin (H&E) and Picrosirius Red (PSR) staining were used to confirm fibrosis in the livers. The jaws were analysed using H&E staining, immunohistochemical assays of interleukin (IL)‐1β, IL‐6 and tumour necrosis factor‐alpha (TNF‐α). Student’s t‐test and Mann–Whitney’s U‐test were used for statistical analysis (P < 0.05).
Results
Inflammatory infiltrate was moderate in the AP group and severe in the AP + LF group (P < 0.05). Periapical bone resorption was significantly larger in the AP + LF group compared with the AP group (P < 0.05). IL‐1β, IL‐6 and TNF‐α levels were significantly higher in AP + LF group when compared to the AP group (P < 0.05).
Conclusion
More intense inflammatory infiltrate, greater amounts of pro‐inflammatory cytokines and increased periapical bone resorption were observed in the presence of liver fibrosis in rats with exposed pulps.
Highlights • Using a model of neonatal excitotoxic brain injury, we shows an early opening of the BBB that likely contributes to damage. • In this model, we demonstrate that melatonin specifically ...prevents this early BBB alteration. • Our study shows an early BBB disruption in perinatal damage and further extend the neuroprotective profile of melatonin.
Seagrass shoots interact with hydrodynamic forces and thereby a positively or negatively influence the survival of associated species. The modification of these forces indirectly alters the physical ...transport and flux of edible particles within seagrass meadows, which will influence the growth and survivorship of associated filter-feeding organisms. The present work contributes to gaining insight into the mechanisms controlling the availability of resources for filter feeders inhabiting seagrass canopies, both from physical (influenced by seagrass density and patchiness) and biological (regulated by filter feeder density) perspectives. A factorial experiment was conducted in a large racetrack flume, which combined changes in hydrodynamic conditions, chlorophyll a concentration in the water and food intake rate (FIR) in a model active filter-feeding organism (the cockle). Results showed that seagrass density and patchiness modified both hydrodynamic forces and availability of resources for filter feeders. Chlorophyll a water content decreased to 50% of the initial value when densities of both seagrass shoots and cockles were high. Also, filter feeder density controlled resource availability within seagrass patches, depending on its spatial position within the racetrack flume. Under high density of filter-feeding organisms, chlorophyll a levels were lower between patches. This suggests that the pumping activity of cockles (i.e. biomixing) is an emergent key factor affecting both resource availability and FIR for filter feeders in dense canopies. Applying our results to natural conditions, we suggest the existence of a direct correlation between habitat complexity (i.e. shoot density and degree of patchiness) and filter feeders density. Fragmented and low-density patches seem to offer both greater protection from hydrodynamic forces and higher resource availability. In denser patches, however, resources are allocated mostly within the canopy, which would benefit filter feeders if they occurred at low densities, but would be limiting when filter feeder were at high densities.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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