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Abstract The Antarctic krill Euphausia superba is a key species in Antarctic waters, mainly because it is a major component of the diet of dominant predators, including penguins. It is also a marine living resource that is commercially harvested. Since 2000, krill fishing has become more concentrated. On the basis of several years of data, it has been reported that up to 57% of the krill fishery harvests occur in the Bransfield Strait area. The distribution of krill in the Southern Ocean is not well described. Studies that compare the size of krill caught by commercial vessels with that recorded in the diet of predators are even rarer. The main objectives of this study were to assess the spatial diversity in the size and putative age of krill in the CCAMLR subarea 48.1, to investigate the spatial availability of krill and its size and age structure, and to assess whether the diet of Pygoscelis penguins reflects the size structure of krill present in the environment. The results implied that the size and age structure of the krill population were similar throughout the Bransfield Strait during the study period, although those in the eastern and southern parts of the strait and the Brabant Island region were the most similar. The Livingston Island and Drake Passage areas were clearly distinguishable from the above regions, where larger and therefore older krill were recorded. All Pygoscelis penguin species showed size preferences for consumed krill; therefore, their diet is likely not a reliable indicator of the size of krill in the environment. Krill that had not yet reached sexual maturity, and thus not yet started reproducing were commercially caught in the Bransfield Strait during the investigated years.

Abstract The global climate change is mainly caused by carbon dioxide (CO2) emissions. To help reduce CO2 emissions and conserve thermal energy, sustainable materials based on flexible thermal insulation are developed to minimize heat flux, drawing inspiration from natural systems such as polar bear hairs. The unique structure of hollow double‐shell fibers makes it possible to achieve low thermal conductivity in the material while retaining exceptional elasticity, allowing it to adapt to insulation systems of any shape. The layered system of porous mats reaches a thermal conductivity coefficient of 0.031 W∙m⁻¹∙K⁻¹ and enables to reduce the heat transfer. The results achieved using scanning thermal microscopy (SThM) correlate with the simulated heat flow in the case of individual fibers. This research study brings new insights into the energy efficiency of domestic environments, thereby addressing the growing demand for sustainable and high‐performance insulation materials for saving energy loss and reducing pollution footprint.

ObjectiveThis systematic review examined the effectiveness of Emergency Department-based and initiated youth suicide prevention interventions for suicide attempts, suicidal ideation, hospitalization, family system functioning, and other mental health symptoms.MethodsWe searched five databases for randomized controlled trial (RCT) studies that examined Emergency Department-based and initiated suicide prevention interventions among youth aged 10 to 18 years old between May 2020 to June 2022. Using Cohen's d and 95% confidence interval as our standardised metrics, we followed the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) and Synthesis Without Meta-Analysis in Systematic Reviews (SWiM) guidelines when synthesizing, interpreting, and reporting the findings of this review.ResultsFive studies were included in this review. Findings were first synthesized according to the targeted population of the study intervention and this review's outcomes. Two interventions were effective for decreasing depressive symptoms, hospitalization recidivism, and/or increasing family empowerment. There were no interventions that reduced subsequent suicide attempts. A meta-analysis was not conducted due to the heterogeneity of the data.ConclusionA need exists to develop and evaluate Emergency Department-based and initiated youth suicide prevention interventions that can be successfully and sustainably implemented in practice. Future research should focus on evaluating the components of interventions that effectively mitigate suicide risk among high-risk youth.

Abstract Urolithin A (UA, 1), a gut microbiota postbiotic metabolite is attributed to express interesting biological activities indicated by in vitro, in vivo and clinical studies. Due to its strong anti-inflammatory properties it is considered as a promising lead molecule for further drug development, however, its strong phase II metabolism, severely limits its oral application. Therefore, monoesterified UA derivatives with selected NSAIDs: ibuprofen (Mix 3a/3b), mefenamic acid (Mix 4a/4b), diclofenac (Mix 5a/5b) and aspirin (Mix 6a/6b) were designed. Performed array of stability assays indicated Mix 4a/4b as a most suitable candidate for further studies due to its exceptional stability in human plasma. Thus, we evaluated effects of Mix 4a/4b on cell viability as well as the impact on cytokines secretion in THP-1 derived macrophages and compared it to UA. At high concentration (50 µM) Mix 4a/4b expressed a cytotoxic effect, however at concentration of 5 µM it significantly suppressed TNF-α secretion, and significantly increased ani-inflammatory IL-10 secretion at 10 µM without affecting cell viability. This work has led to selection of a novel UA derivatives, which are stable in solutions and in human plasma as well as posess anti-inflammatory activity towards THP-1 macrophages at non-cytotoxic concentrations.

Infants’ limb movements evolve from disorganized to more selectively coordinated during the first year of life as they learn to navigate and interact with an ever-changing environment more efficiently. However, how these coordination patterns change during the first year of life and across different contexts is unknown. Here, we used wearable motion trackers to study the developmental changes in the complexity of limb movements (arms and legs) at 4, 6, 9 and 12 months of age in two different tasks: rhythmic rattle-shaking and free play. We applied Multidimensional Recurrence Quantification Analysis (MdRQA) to capture the nonlinear changes in infants’ limb complexity. We show that the MdRQA parameters (entropy, recurrence rate and mean line) are task-dependent only at 9 and 12 months of age, with higher values in rattle-shaking than free play. Since rattle-shaking elicits more stable and repetitive limb movements than the free exploration of multiple objects, we interpret our data as reflecting an increase in infants’ motor control that allows for stable body positioning and easier execution of limb movements. Infants’ motor system becomes more stable and flexible with age, allowing for flexible adaptation of behaviors to task demands.

A goal of tracking migratory animals is to characterize the habitats they use and to interpret population processes with respect to conditions experienced en route to, and within, overwintering areas. For migratory seabirds with broad breeding ranges, inferring population-level effects of environmental conditions that are experienced during migratory periods would benefit by directly comparing how birds from different breeding aggregations disperse, characterizing the physical conditions of areas they use, and determining whether they occupy shared foraging areas. We therefore tracked 41 adult and juvenile chinstrap penguins (Pygoscelis antarctica) from three breeding locations in the northern Antarctic Peninsula region during the austral winter of 2017. The satellite tracking data revealed overlap of individuals over continental shelf areas during autumn months (Mar-May), shared outbound corridors that track the southern Antarctic circumpolar current front, followed by occupancy of progressively colder, deeper, and ice-free waters that spanned the entire western hemisphere south of the Polar Front. Despite broadly similar physical environments used by individuals from different colonies, the proportion of birds from each colony that remained within 500km of their colony was positively correlated with their local population trends. This suggests that local migration strategies near the Antarctic Peninsula may benefit breeding populations. However, the magnitude of inter-colony and intra-colony overlap was generally low given the broad scale of habitats occupied. High individual variation in winter movements suggests that habitat selection among chinstrap penguins is more opportunistic, without clear colony-specific preference for fine-scale foraging hotspots. Mixing of individuals from multiple colonies across broad regions of the Southern Ocean would expose chinstrap penguins from the Antarctic Peninsula to a shared environmental experience that helps explain the regional decline in their abundance.

The aim of this article is to show geomorphological mapping of remote Antarctic locations using images taken by a fixed-wing unmanned aerial vehicle (UAV) during the Beyond Visual Line of Sight (BVLOS) operations. We mapped landform assemblages developed in forelands of Ecology Glacier (EGF), Sphinx Glacier (SGF) and Baranowski Glacier (BGF) in Antarctic Specially Protected Area No. 128 (ASPA 128) on King George Island (South Shetland Islands) and inferred about glacial dynamics. The orthophoto and digital elevation model allowed for geomorphological mapping of glacial forelands, including (i) glacial depositional landforms, (ii) fluvial and fluvioglacial landforms, (iii) littoral and lacustrine landforms, (iv) bodies of water, and (v) other. The largest area is occupied by ground moraine and glacial lagoons on EGF and BGF. The most profound features of EGF are the large latero-frontal moraine ridges from Little Ice Age and the first half of the 20th century. Large areas of ground moraine, frequently fluted and marked with large recessional moraine ridges, dominate on SGF. A significant percentage of bedrock outcrops and end moraine complexes characterize BGF. The landform assemblages are typical for discontinuous fast ice flow of tidewater glaciers over a deformable bed. It is inferred that ice flow velocity decreased as a result of recession from the sea coast, resulting in a significant decrease in the length of ice cliffs and decrease in calving rate. Image acquisition during the fixed-wing UAV BVLOS operation proved to be a very robust technique in harsh polar conditions of King George Island.

AIMS:Studies in global androgen receptor knockout (G-ARKO) and orchidectomised mice suggest that androgen accelerates reperfusion of the ischaemic hindlimb by stimulating angiogenesis. This investigation used novel, vascular cell-specific ARKO mice to address the hypothesis that the impaired hindlimb reperfusion in G-ARKO mice was due to loss of AR from cells in the vascular wall. METHODS AND RESULTS:Mice with selective deletion of AR (ARKO) from vascular smooth muscle cells (SM-ARKO), endothelial cells (VE-ARKO), or both (SM/VE-ARKO) were compared with wild type (WT) controls. Hindlimb ischaemia was induced in these mice by ligation and removal of the femoral artery. Post-operative reperfusion was reduced in SM-ARKO and SM/VE-ARKO mice. Immunohistochemistry indicated that this was accompanied by a reduced density of smooth muscle actin-positive vessels but no change in the density of isolectin B4-positive vessels in the gastrocnemius muscle. Deletion of AR from the endothelium (VE-ARKO) did not alter post-operative reperfusion or vessel density. In an ex vivo (aortic ring culture) model of angiogenesis, AR was not detected in vascular outgrowths and angiogenesis was not altered by vascular ARKO or by exposure to dihydrotestosterone (DHT 10(-10)-10(-7)M; 6 days). CONCLUSION:These results suggest that loss of AR from vascular smooth muscle, but not from the endothelium, contributes to impaired reperfusion in the ischaemic hindlimb of G-ARKO. Impaired reperfusion was associated with reduced collateral formation rather than reduced angiogenesis.

In the paper, we consider local aspects of the entropy of nonautonomous dynamical systems. For this purpose, we introduce the notion of a (asymptotical) focal entropy point. The notion of entropy appeared as a result of practical needs concerning thermodynamics and the problem of information flow, and it is connected with the complexity of a system. The definition adopted in the paper specifies the notions that express the complexity of a system around certain points (the complexity of the system is the same as its complexity around these points), and moreover, the complexity of a system around such points does not depend on the behavior of the system in other parts of its domain. Any periodic system “acting” in the closed unit interval has an asymptotical focal entropy point, which justifies wide interest in these issues. In the paper, we examine the problems of the distortions of a system and the approximation of an autonomous system by a nonautonomous one, in the context of having a (asymptotical) focal entropy point. It is shown that even a slight modification of a system may lead to the arising of the respective focal entropy points.

Campylobacteriosis is the most frequent zoonosis in developed countries and various domestic animals can function as reservoir for the main pathogens Campylobacter jejuni and Campylobacter coli. In the present study we compared population structures of 730 C. jejuni and C. coli from human cases, 610 chicken, 159 dog, 360 pig and 23 cattle isolates collected between 2001 and 2012 in Switzerland. All isolates had been typed with multi locus sequence typing (MLST) and flaB-typing and their genotypic resistance to quinolones was determined. We used complementary approaches by testing for differences between isolates from different hosts with the proportion similarity as well as the fixation index and by attributing the source of the human isolates with Bayesian assignment using the software STRUCTURE. Analyses were done with MLST and flaB data in parallel and both typing methods were tested for associations of genotypes with quinolone resistance. Results obtained with MLST and flaB data corresponded remarkably well, both indicating chickens as the main source for human infection for both Campylobacter species. Based on MLST, 70.9% of the human cases were attributed to chickens, 19.3% to cattle, 8.6% to dogs and 1.2% to pigs. Furthermore we found a host independent association between sequence type (ST) and quinolone resistance. The most notable were ST-45, all isolates of which were susceptible, while for ST-464 all were resistant.

The risks of long term sequelae from childhood pneumonia have not been systematically assessed. The aims of this study were to: (i) estimate the risks of respiratory sequelae after pneumonia in children under five years; (ii) estimate the distribution of the different types of respiratory sequelae; and (iii) compare sequelae risk by hospitalisation status and pathogen.We systematically reviewed published papers from 1970 to 2011. Standard global burden of disease categories (restrictive lung disease, obstructive lung disease, bronchiectasis) were labelled as major sequelae. 'Minor' sequelae (chronic bronchitis, asthma, other abnormal pulmonary function, other respiratory disease), and multiple impairments were also included. Thirteen papers were selected for inclusion. Synthesis was by random effects meta-analysis and meta-regression.Risk of at least one major sequelae was 5.5% (95% confidence interval [95% CI] 2.8-8.3%) in non hospitalised children and 13.6% [6.2-21.1%]) in hospitalised children. Adenovirus pneumonia was associated with the highest sequelae risk (54.8% [39.2-70.5%]) but children hospitalised with no pathogen isolated also had high risk (17.6% [10.9-24.3%]). The most common type of major sequela was restrictive lung disease (5.4% [2.5-10.2%]) . Potential confounders such as loss to follow up and median age at infection were not associated with sequelae risk in the final models.All children with pneumonia diagnosed by a health professional should be considered at risk of long term sequelae. Evaluation of childhood pneumonia interventions should include potential impact on long term respiratory sequelae.