Decadal trends in air-sea CO2 exchange in the Ross Sea (Antarctica)

Abstract Highly productive Antarctic shelf systems, like the Ross Sea, play important roles in regional carbon budgets, but the drivers of local variations are poorly quantified. We assess the variability in the Ross Sea carbon cycle using a regional physical‐biogeochemical model. Regionally, total partial pressure of CO2 (pCO2) increases are largely controlled by the biological pump and broadly similar to those in the offshore Southern Ocean. However, this masks substantial local variability within the Ross Sea, where interannual fluctuations in total pCO2 are driven by the biological pump and alkalinity, whereas those for anthropogenic pCO2 are related to physical processes. Overall, the high degree of spatial variability in the Ross Sea carbon cycle causes extremes in aragonite saturation that can be as large as long‐term trends. Therefore, Antarctic shelf polynya systems like the Ross Sea will be strongly affected by local processes in addition to larger‐scale phenomena

Different substrates of non-sustained ventricular tachycardia in post-infarction patients with and without left ventricular dilatation

Background: We investigated the relationship between nonsustained ventricular tachycardia (NSVT) and left ventricular (LV) dilatation, function, remodeling, and scar tissue extent in patients with previous myocardial infarction (MI). Methods and Results: Eighty-two patients (ages 64610 years) with first previous MI were referred for 24-hour electrocardiogram recording and cine and delayed enhancement (DE) cardiac magnetic resonance (CMR). LVvolumes, ejection fraction, systolic wall thickening, sphericity index, and core and peri-infarctual areas of scar tissue by CMR were evaluated. LV dilatation was observed in 39 patients. Episodes of NSVT were recorded in 32 patients: 23 with LV dilatation and 9 without. In the entire population, NSVTwas related to ejection fraction, LV volumes, LV mass, and sphericity index; end-systolic volume (P5.001) resulted in the only independent predictor at multivariate analysis. In patients without LV dilatation, the occurrence of NSVTwas only positively related with percentage of contracting segments with DE (P5.008). Conversely, in patients with LV dilatation, increase in LV mass (P5.020) and end-systolic volume (P5.038) were independent predictors of NSVT. Conclusions: Necrotic and viable myocardium coexistence within the same wall segments predicted occurrence of NSVT in patients without LV dilatation, whereas LV mass and end-systolic volume were predictors of NSVT in those with LV dilatation. (J Cardiac Fail 2010;16:61e68

Designing social immersive virtual environments for the Metaverse: The case study of MetaLibrary

Background: Over the last years, the rapid advancement of technology has led to the development of many approaches to digitalization. In this respect, the Metaverse is providing 3D, persistent virtual environments that can be used to access digital content, meet virtually, and carry out a number of professional and leisure tasks. Among the numerous technologies supporting the Metaverse, a primary role is played by immersive Virtual Reality (VR) and its ability to offer highly interactive, social experiences. Despite the growing interest in this area, there are no clear design guidelines for creating environments tailored to the Metaverse. Methods: This paper seeks to advance the research in this area by moving from the study of state of the art on the design of immersive virtual environments in the context of the Metaverse and proposing how to integrate cutting-edge technologies within this context. Specifically, best practices were identified by i) analyzing literature studies focused on human behavior in immersive virtual environments, ii) extracting common features of existing social VR platforms, and iii) performing interviews with experts of a specific application domain. More specifically, the current work considers as a case study the creation of a new virtual environment for MetaLibrary, a VR-based social platform aimed to integrate public libraries into the Metaverse. For the development of the virtual environment, several implementation challenges and additional needs were identified. These elements were considered for the selection of specific cutting-edge technologies and their integration in the development process. A user study was also carried out to investigate some design aspects (namely, lighting conditions and richness of the scene layout) for which deriving clear indications from the above analysis was not possible, since different alternative configurations could be chosen. Results: The work reported in this paper seeks to bridge the gap between existing VR platforms and related literature in the field, on the one hand, and requirements regarding immersive virtual environments for the Metaverse, on the other hand, by reporting a set of best practices which were used to build a social virtual environment that meets users’ expectations and needs. Conclusions: Results suggest that carefully designed virtual environments can positively impact user experience and interaction within the Metaverse. The insights gained with this work offer valuable cues for developing immersive virtual environments for the Metaverse able to deliver ever more effective and engaging experiences

Advances in Technologies for Highly Active Omega-3 Fatty Acids from Krill Oil: Clinical Applications

Euphausia superba, commonly known as krill, is a small marine crustacean from the Antarctic Ocean that plays an important role in the marine ecosystem, serving as feed for most fish. It is a known source of highly bioavailable omega-3 polyunsaturated fatty acids (eicosapentaenoic acid and docosahexaenoic acid). In preclinical studies, krill oil showed metabolic, anti-inflammatory, neuroprotective and chemo preventive effects, while in clinical trials it showed significant metabolic, vascular and ergogenic actions. Solvent extraction is the most conventional method to obtain krill oil. However, different solvents must be used to extract all lipids from krill because of the diversity of the polarities of the lipid compounds in the biomass. This review aims to provide an overview of the chemical composition, bioavailability and bioaccessibility of krill oil, as well as the mechanisms of action, classic and non-conventional extraction techniques, health benefits and current applications of this marine crustacean

Adrenomedullin : a marker of impaired hemodynamics, organ dysfunction, and poor prognosis in cardiogenic shock

Background: The clinical CardShock risk score, including baseline lactate levels, was recently shown to facilitate risk stratification in patients with cardiogenic shock (CS). As based on baseline parameters, however, it may not reflect the change in mortality risk in response to initial therapies. Adrenomedullin is a prognostic biomarker in several cardiovascular diseases and was recently shown to associate with hemodynamic instability in patients with septic shock. The aim of our study was to evaluate the prognostic value and association with hemodynamic parameters of bioactive adrenomedullin (bio-ADM) in patients with CS. Methods: CardShock was a prospective, observational, European multinational cohort study of CS. In this sub-analysis, serial plasma bio-ADM and arterial blood lactate measurements were collected from 178 patients during the first 10 days after detection of CS. Results: Both bio-ADM and lactate were higher in 90-day non-survivors compared to survivors at all time points (P <0.05 for all). Lactate showed good prognostic value during the initial 24 h (AUC 0.78 at admission and 0.76 at 24 h). Subsequently, lactate returned normal ( 55.7 pg/mL) at 48 h compared to those with low bio-ADM levels (49.1 vs. 22.6%, P = 0.001). High levels of bio-ADM were associated with impaired cardiac index, mean arterial pressure, central venous pressure, and systolic pulmonary artery pressure during the study period. Furthermore, high levels of bio-ADM at 48 to 96 h were related to persistently impaired cardiac and end-organ function. Conclusions: Bio-ADM is a valuable prognosticator and marker of impaired hemodynamics in CS patients. High levels of bio-ADM may show shock refractoriness and developing end-organ dysfunction and thus help to guide therapeutic approach in patients with CS.Peer reviewe

Phenoxy resin-based vinylogous urethane covalent adaptable networks

This work presents a post-polymerization approach to the preparation of vitrimers, exploiting the transamination of vinylogous urethane in linear phenoxy resins. Phenoxy vitrimers are obtained by a two-steps synthesis from a commercial phenoxy resin via partial conversion of hydroxyl groups to acetoacetates (AcAc), followed by network formation by reaction with m-xylylendiamine (XYDIA) as crosslinker. Three different vitrimers with variable crosslinking density are obtained by tuning the density of AcAc moieties along the phenoxy resin scaffold (5%, 10% and 15% conversion of hydroxyl groups). The conversion of linear polymers to dynamic crosslinked networks is confirmed by Dynamic Mechanical Thermal Analyzer (DMTA) and rheology measurements, followed by stress relaxation tests to investigate the kinetics of bond exchanges. Tensile tests as a function of reprocessing cycles reveal an increase of the maximum elongation and stress at break and prove the good recyclability of the vitrimers. Enhanced adhesive properties compared to pristine phenoxy resins are demonstrated, including the possibility to thermally re-join the assembly after its mechanical failure. Finally, the solvent-free preparation of vitrimer is explored for 5% crosslinked vitrimer via melt reactive blending, providing a valuable alternative to the less environmentally sustainable synthesis in solution

Multicentric Case-Control Study on Azathioprine Dose and Pharmacokinetics in Early-onset Pediatric Inflammatory Bowel Disease

BACKGROUND: Early-onset inflammatory bowel disease (IBD) is generally aggressive, with a high probability of complications and need of surgery. Despite the introduction of highly effective biological drugs, treatment with azathioprine continues to be important even for early-onset IBD; however, in these patients azathioprine response seems to be reduced. This study evaluated azathioprine doses, metabolite concentrations, and their associations with patients' age in children with IBD treated at 6 tertiary pediatric referral centers. METHODS: Azathioprine doses, metabolites, and clinical effects were assessed after at least 3 months of therapy in 17 early-onset (age 12 and <18 yrs, controls) patients with IBD. Azathioprine dose was titrated on therapeutic efficacy (response and adverse effects). Azathioprine metabolites and thiopurine methyltransferase activity were determined by high-performance liquid chromatography with ultra violet-vis detection (HPLC-UV) methods. RESULTS: Frequency of patients in remission was similar among early-onset and control groups, respectively (82% and 84%, P value = 0.72). Early-onset patients required higher doses of azathioprine (median 2.7 versus 2.0 mg\ub7kg\ub7d, P value = 1.1 7 10). Different doses resulted in comparable azathioprine active thioguanine nucleotide metabolite concentrations (median 263 versus 366 pmol/8 7 10 erythrocytes, P value = 0.41) and methylmercaptopurine nucleotide concentrations (median 1455 versus 1532 pmol/8 7 10 erythrocytes, P value = 0.60). Lower ratios between thioguanine nucleotide metabolites and azathioprine doses were found in early-onset patients (median 98 versus 184 pmol/8 7 10 erythrocytes\ub7mg\ub7kg\ub7d, P value = 0.017). Interestingly, early-onset patients presented also higher thiopurine methyltransferase activity (median 476 versus 350 nmol methylmercaptopurine/mg hemoglobin/h, P-value = 0.046). CONCLUSIONS: This study demonstrated that patients with early-onset IBD present increased inactivating azathioprine metabolism, likely because of elevated activity of the enzyme thiopurine methyltransferase

New OCT and OCTA Insights in Inherited Retinal Dystrophies

Optical coherence tomography (OCT) and OCT angiography (OCTA) radically changed the diagnostics of inherited retinal dystrophies (IRD), providing new information regarding the microstructural changes occurring in each disease. The introduction of quantitative metrics provided even more steps forward in the understanding of IRD pathogenesis and course, allowing to propose new ways to categorize different subgroups of patients, characterized by remarkably different characteristics and prognosis. All these informations provided insights regarding how heterogeneous the clinical spectrum of IRD is. In the present study, we provide an updated description of OCT and OCTA findings in the main IRD, including retinitis pigmentosa, Stargardt disease, and Best vitelliform macular dystrophy. Moreover, we discuss imaging findings in pigmented paravenous retinochoroidal atrophy, a rare condition that is undergoing even growing scientific and clinical interest. In addition, we provided a brief updated scenario on imaging findings in pattern dystrophies. We discuss in detail the current state-of-the-art and the new insights provided by quantitative OCT and OCTA approaches, offering a complete description that might be helpful both for expert and nonexpert researchers interested in IRD

Incidence, Characteristics, and Outcomes of Macular Neovascularization in Extensive Macular Atrophy with Pseudodrusen-like Appearance

Purpose:To report the incidence, features, and clinical outcomes of macular neovascularization (MNV) in a large Italian cohort of patients with extensive macular atrophy with pseudodrusen-like appearance (EMAP).Methods:Retrospective, longitudinal study including 79 EMAP patients (158 eyes) with ≥6 months of follow-up at three retina clinics. Medical records and imaging were reviewed for demographic and clinical data, including age, best-corrected visual acuity (BCVA), MNV features, and retinal pigment epithelium (RPE) atrophy size, measured by short-wavelength autofluorescence and refined with near-infrared and OCT imaging. Main outcomes included cumulative MNV incidence, MNV risk factors, and BCVA and RPE atrophy changes in eyes with and without MNV.Results:Over a mean follow-up of 40.4 months, MNV developed in 14 eyes (10 patients), with a 4-year cumulative incidence of 15.2%. Most MNVs were type 2 (86%) and subfoveal (64%). Cox regression identified younger age, fellow eye involvement, smaller RPE atrophy size, and greater central subfield thickness (all p&lt;0.01) as significant risk factors for MNV. While eyes with MNV had lower baseline BCVA (58.4 vs. 71.4 letters, approximately 20/63 vs. 20/40 Snellen; p=0.005), BCVA decline over time was similar between the two groups (-3.9 vs. -4.1 letters/year, p=0.69). However, RPE atrophy progressed faster in MNV eyes (3.4 vs. 2.8 mm2/year, p=0.02).Conclusions:In this EMAP cohort, MNV had a cumulative incidence of 15.2% at 4 years. Although BCVA outcomes were comparable, MNV was associated with faster atrophy progression, potentially due to a more aggressive disease phenotype or fibro-atrophic changes