The impacts of alien species on river bioassessment.

The extent of alien taxa impacts on river ecosystem health is unclear, but their frequency continues to rise. We investigated 1) the prevalence of including alien taxa in common bioindicators used in river bioassessment, 2) the effect of alien taxa on the richness and abundance of natives, and 3) whether including alien taxa in bioassessment tools increased their sensitivity to river degradation. In the 17 countries analyzed fish represented the greatest number of alien species (1726), followed by macrophytes (925), macroinvertebrates (556), and diatoms (7).

Pulmonary Embolism of COVID-19: A Year of Reflection.

Introduction The coronavirus disease 2019 (COVID-19) pandemic has brought about significant changes in the medical field. While primarily characterized as a respiratory syndrome, COVID-19 is also associated with vascular events, particularly thrombotic complications. These events can manifest as initial presentations or develop as complications during the course of the disease, predominantly driven by immune-mediated mechanisms.

Fish and macroinvertebrate assemblages reveal extensive degradation of the world's rivers.

Rivers suffer from multiple stressors acting simultaneously on their biota, but the consequences are poorly quantified at the global scale. We evaluated the biological condition of rivers globally, including the largest proportion of countries from the Global South published to date. We gathered macroinvertebrate- and fish-based assessments from 72,275 and 37,676 sites, respectively, from 64 study regions across six continents and 45 nations.

Effect of environmental education on the knowledge of aquatic ecosystems and reconnection with nature in early childhood.

Blue and green ecosystems are considered a key for the improvement of cities sustainability, providing numerous ecosystem services and habitat for many species. However, urban streams are still neglected and degraded, specially in southern European countries. One important step towards the rehabilitation of these ecosystems is the awareness of their importance by citizens.

Assessing changes in stream macroinvertebrate communities across ecological gradients using morphological versus DNA metabarcoding approaches.

Freshwater macroinvertebrates provide valuable indicators for biomonitoring ecosystem change in relation to natural and anthropogenic drivers. DNA metabarcoding is an efficient approach for estimating such indicators, but its results may differ from morphotaxonomic approaches traditionally used in biomonitoring. Here we test the hypothesis that despite differences in the number and identity of taxa recorded, both approaches may retrieve comparable patterns of community change, and detect similar ecological gradients influencing such changes.

Influence of river regulation and instream habitat on invertebrate assemblage' structure and function.

Dams modify geomorphology, water quantity, quality and timing of stream flows affecting ecosystem functioning and aquatic biota. In this study, we addressed the structural and functional macroinvertebrate community alterations in different instream mesohabitats of two Portuguese rivers impaired by dams. We sampled macroinvertebrates in riffles, runs and pools of river sites downstream of the dams (i.

Modelling technical and biological biases in macroinvertebrate community assessment from bulk preservative using multiple metabarcoding markers.

DNA metabarcoding from the ethanol used to store macroinvertebrate bulk samples is a convenient methodological option in molecular biodiversity assessment and biomonitoring of aquatic ecosystems, as it preserves specimens and reduces problems associated with sample sorting. However, this method may be affected by errors and biases, which need to be thoroughly quantified before it can be mainstreamed into biomonitoring programmes. Here, we used 80 unsorted macroinvertebrate samples collected in Portugal under a Water Framework Directive monitoring programme, to compare community diversity and taxonomic composition metrics estimated through morphotaxonomy versus metabarcoding from storage ethanol using three markers (COI-M19BR2, 16S-Inse01 and 18S-Euka02) and a multimarker approach.

Exploring the intramolecular catalysis of the proton exchange process to modulate the relaxivity of Gd(iii)-complexes of HP-DO3A-like ligands.

The Gd(iii)-complexes of three novel HP-DO3A-like ligands have been investigated to assess the relationship between relaxometry and intramolecular catalysis of the proton exchange. The structures of these ligands differ from the parent HP-DO3A because the methyl group of the hydroxy-propyl arm has been replaced by -Ph-OH, -Ph-NH2 and -Ph-COOH, respectively. The phenol, amine and carboxylate functionalities display an intramolecular H-bonding with the coordinated hydroxyl moiety that affects either the pK values of the involved functionalities and the rate of the proton exchange process.

Chemical exchange saturation transfer MRI shows low cerebral 2-deoxy-D-glucose uptake in a model of Alzheimer's Disease.

Glucose is the central nervous system's only energy source. Imaging techniques capable to detect pathological alterations of the brain metabolism are useful in different diagnostic processes. Such techniques are also beneficial for assessing the evaluation efficacy of therapies in pre-clinical and clinical stages of diseases.

Exploiting the Proton Exchange as an Additional Route to Enhance the Relaxivity of Paramagnetic MRI Contrast Agents.

The relaxivity of Gd(HP-DO3A) was studied as a function of pH and buffer composition in order to identify the main factors of the observed relaxation enhancement due to the exchange of the coordinated hydroxyl proton. It was established that the paramagnetic relaxation time, T, of the coordinated hydroxyl proton is about 50% shorter than that of the protons in the coordinated water molecule. The control of the p K of the coordinated alcoholic -OH moiety in the ligand is fundamental to utilize the proton exchange enhanced relaxivity under physio/pathologic conditions.

Chironomidae traits and life history strategies as indicators of anthropogenic disturbance.

In freshwater ecosystems, Chironomidae are currently considered indicators of poor water quality because the family is often abundant in degraded sites. However, it incorporates taxa with a large ecological and physiological diversity and different sensitivity to impairment. Yet, the usual identification of Chironomidae at coarse taxonomic levels (family or subfamily) masks genus and species sensitivities.

Adjusting the effect of seasonal variability in the bioassessment of streams.

Bioassessment tools should distinguish between the effects of anthropogenic degradation in communities and natural temporal changes. The present study tests the influence of natural seasonal variability on macroinvertebrate stream communities assessed by a predictive model (PORTRIV) and a multimetric index (IPtI) calibrated for spring. The scores of PORTRIV decreased significantly between spring and autumn, and between spring and winter (ca.

Hyperpolarized [1,3-13C2 ]ethyl acetoacetate is a novel diagnostic metabolic marker of liver cancer.

An increased prevalence of liver diseases such as hepatitis C and nonalcoholic fatty liver results in an augmented incidence of the most common form of liver cancer, hepatocellular carcinoma (HCC). HCC is most often found in the cirrhotic liver and it can therefore be challenging to rely on anatomical information alone when diagnosing HCC. Valuable information on specific cellular metabolism can be obtained with high sensitivity thanks to an emerging magnetic resonance (MR) technique that uses 13C labeled hyperpolarized molecules.

Relevance of electron spin dissipative processes to dynamic nuclear polarization via thermal mixing.

The available theoretical approaches aiming at describing Dynamic Nuclear spin Polarization (DNP) in solutions containing molecules of biomedical interest and paramagnetic centers are not able to model the behaviour observed upon varying the concentration of trityl radicals or the polarization enhancement caused by moderate addition of gadolinium complexes. In this manuscript, we first show experimentally that the nuclear steady state polarization reached in solutions of pyruvic acid with 15 mM trityl radicals is substantially independent on the average internuclear distance. This evidences a leading role of electron (over nuclear) spin relaxation processes in determining the ultimate performances of DNP.

On the role of electron-nucleus contact and microwave saturation in thermal mixing DNP.

We have explored the manifold physical scenarios emerging from a model of Dynamic Nuclear Polarization (DNP) via thermal mixing under the hypothesis of highly effective electron-electron interaction. When the electron and nuclear reservoirs are also assumed to be in strong thermal contact and the microwave irradiation saturates the target electron transition, the enhancement of the nuclear polarization is expected to be considerably high even if the irradiation frequency is set far away from the centre of the ESR line (as already predicted by Borghini) and the typical polarization time is reduced on moving towards the boundaries of the said line. More reasonable behaviours are obtained by reducing the level of microwave saturation or the contact between electrons and nuclei in the presence of nuclear leakage.

Electron and nuclear spin dynamics in the thermal mixing model of dynamic nuclear polarization.

A novel mathematical treatment is proposed for computing the time evolution of dynamic nuclear polarization processes in the low temperature thermal mixing regime. Without assuming any a priori analytical form for the electron polarization, our approach provides a quantitative picture of the steady state that agrees with the well known Borghini prediction based on thermodynamic arguments, as long as the electrons-nuclei transition rates are fast compared to the other relevant time scales. Substantially different final polarization levels are achieved instead when the latter assumption is relaxed in the presence of a nuclear leakage term, even though very weak, suggesting a possible explanation for the deviation between the measured steady state polarizations and the Borghini prediction.

E-3810 is a potent dual inhibitor of VEGFR and FGFR that exerts antitumor activity in multiple preclinical models.

Tumor angiogenesis is a degenerate process regulated by a complex network of proangiogenic factors. Existing antiangiogenic drugs used in clinic are characterized by selectivity for specific factors. Antiangiogenic properties might be improved in drugs that target multiple factors and thereby address the inherent mechanistic degeneracy in angiogenesis.

[Alpha-1 antitrypsin deficiency. Two case reports].

The alpha-1 antitrypsin deficiency is an hereditary autosomic codominant disease. The phenotype Pi ZZ is associated more frequently with pulmonary disease and is responsible for the presence of emphysema early in life, particularly in smokers. The author's present two cases which diagnosis were performed later in life and in which other factors could be also responsible for clinical manifestations.