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Legacies of temperature fluctuations promote stability in marine biofilm communities
No full textThe increasing frequency and intensity of extreme climate events are driving significant biodiversity shifts across ecosystems. Yet, the extent to which these climate legacies will shape the response of ecosystems to future perturbations remains poorly understood. Here, we tracked taxon and trait dynamics of rocky intertidal biofilm communities under contrasting regimes of warming (fixed vs. fluctuating) and assessed how they influenced stability dimensions in response to temperature extremes. Fixed warming enhanced the resistance of biofilm by promoting the functional redundancy of stress-tolerance traits. In contrast, fluctuating warming boosted recovery rate through the selection of fast-growing taxa at the expense of functional redundancy. This selection intensified a trade-off between stress tolerance and growth further limiting the ability of biofilm to cope with temperature extremes. Anticipating the challenges posed by future extreme events, our findings offer a forward-looking perspective on the stability of microbial communities in the face of ongoing climatic change
Cyclic-elastic behavior in plastically pre-strained lattice structures
No full textThe study investigates the evolution of elastic behavior in lattice structures subjected to cyclical loading after pre-straining to various levels of plastic deformation. Triply Periodic Minimal Surface (TPMS) gyroid lattice specimens were fabricated using the Laser Powder Bed Fusion (L-PBF) technique and subjected to controlled steps of compressive pre-straining, inducing plastic deformations. Subsequently, the specimens underwent cyclic loading-unloading tests to characterize their elastic behavior. Stress-strain curves were monitored throughout the testing to determine the apparent elastic modulus (E*) at each cycle. The results demonstrate that E* of pre-strained lattices are not static. The initial cycles after pre-straining exhibit a change in stiffness, with the E* initially increasing depending on the pre-strain level. This behavior is attributed to the morphology of the lattice itself, which is more sensible to local hardening due to an evident bending-dominated mechanical response. Over slight plastic strains, the elastic modulus stabilizes, reaching a new stiffening-to-plastic strain evolution. The magnitude of this shift and the experimental response's dispersion are found to not be dependent on the pre-strain level
Measurement of the time-integrated CP asymmetry in D0 → KS0 KS0 decays using opposite-side flavor tagging at Belle and Belle II
No full textWe measure the time-integrated CP asymmetry in D-0 -> (KSKS0)-K-0 decays reconstructed in e(+)e(-) -> c (c) over bar events collected by the Belle and Belle II experiments. The corresponding data samples have integrated luminosities of 980 and 428 fb(-1), respectively. To infer the flavor of the D-0 meson, we exploit the correlation between the flavor of the reconstructed decay and the electric charges of particles reconstructed in the rest of the e(+)e(-) -> c (c) over bar event. This results in a sample which is independent from any other previously used at Belle or Belle II. The result, A(CP)(D-0 -> (KSKS0)-K-0) = (1.3 +/- 2.0 +/- 0.2)%, where the first uncertainty is statistical and the second systematic, is consistent with previous determinations and with CP symmetry
Journal of Hazardous Materials
No full textArsenic is a widespread metalloid that even at low concentrations is highly toxic to most plant species. While the
transcriptional responses associated to arsenic tolerance have been widely investigated in vascular plants,
comparatively little is known in their sister lineage, the bryophytes. Most importantly, functional evidence of
whether the same genes play major roles in arsenic tolerance responses in these two anciently diverged land
plant lineages is currently largely missing. In this study, we identified by RNA-Seq a highly reliable set of
differentially expressed genes (DEGs) responding to arsenite toxicity in the model bryophyte Marchantia polymorpha.
We then explored the evolutionary level of functional conservation of seven upregulated DEGs by
Agrobacterium-mediated transformation in the highly arsenic-sensitive cad1–3 mutant of Arabidopsis thaliana as a
representative of tracheophytes, and characterized fresh weight, malondialdehyde production and total arsenic
content in dry biomass of transgenic lines. While two of the tested M. polymorpha DEGs did not significantly
enhance arsenic tolerance, the remaining five DEGs, when overexpressed in cad1–3, conferred maximal levels of tolerance, measured as biomass accumulation, between 56 % and 100 % of WT Col-0 plants. Among them, a putative 1-cys peroxiredoxin restored growth, protection from lipid peroxidation and capacity to accumulate arsenic to levels indistinguishable from those of WT. These results provide functional evidence for the consid
erable conservation of arsenic tolerance responses between M. polymorpha and A. thaliana, suggesting that M. polymorpha can be a valid model for the identification of evolutionarily deeply conserved genes for the genetic improvement of crops for arsenic tolerance
Modulation of test anxiety-induced salivary protein secretion by ovarian steroid hormones: a preliminary study
No full textIn women the menstrual cycle influences mood and anxiety. Aim of this study was to preliminarily investigate whether different ovarian steroid hormone levels may modulate the psychophysiological responses elicited by test anxiety. Specifically, we compared the secretion of anxiety-induced salivary proteins of healthy women in the early follicular (Pre-Ov group) (low ovarian steroid hormones levels) and mid-luteal (Post-Ov group) (medium/high ovarian steroid hormones levels) phase of the menstrual cycle, during the simulation of an oral examination. Saliva samples were collected before and after a relaxation period and at two post-simulation times and analyzed by two-dimensional electrophoresis and western blot. Proteins corresponding to spots differentially expressed in the two groups across the session were identified through mass spectrometry and most of them corresponded to acute stress and/or oral mucosa immunity biomarkers. The task induced an increase in alpha-amylase, carbonic anhydrase and cystatin S, and a decrease in immunoglobulin light/J chains in both groups. Analogous changes in these proteins have previously been linked to psychological or physical stress. However, specific spots corresponding, for example, to cystatins and 14-3-3 protein, changed exclusively in the Pre-Ov group, while prolactin-inducible protein, polymeric immunoglobulin receptor, fragments of alpha-amylase and immunoglobulins only in the Post-Ov group, indicating a potential modulation of their secretion by ovarian steroid hormones. Overall, the results provide preliminary evidence that ovarian steroid hormones may be a driving factor for differences in physiological responses induced by test anxiety. The results are promising, but further validation in a larger sample is needed
Digital Health in clinical practice: an example of an expert system for heart failure management
No full textClinical Decision Support Systems (CDSS) are fundamental tools for assisting physicians in the decision-making process, thanks to their ability to analyze clinical data and provide diagnostic or therapeutic recommendations. The literature classifies them mainly as knowledge-based systems, which employ IF-THEN rules grounded in expert clinical experience, and machine learning systems, which use statistical models to identify data patterns.
Despite their potential, CDSS face limitations hindering their effectiveness and adoption. Many focus solely on single pathologies, overlooking the complexity of comorbidities and the patient’s multidimensional nature. Moreover, a lack of interoperability often necessitates manual data entry, risking errors and incomplete information, which negatively impacts performance. Physician diffidence, stemming from technical issues and perceived limited control, further impedes their
uptake.
Addressing Digital Health (DH) needs requires evolving CDSS toward greater interoperability, telemedicine integration, multidisciplinary management, and personalized care.
Of particular interest is the ongoing challenge of automatically and dynamically calculating individual patient risk for complications or worsening of clinical conditions. This relies on processing real-time data from vital signs, health records, and questionnaires. Integrating this information into a Medical Expert System (MES) could significantly enhance clinical decision support. This article focuses MES characteristics and their role in DH, showing a telemedicine application for managing complex chronic heart failure patients
The interplay between childhood trauma, hopelessness, depressive symptoms, and mental pain in a large sample of patients with severe mental disorders: A network analysis.
No full textBackground: Mental pain represents a significant risk factor for suicidal behavior in severe mental disorders. The present study aims to investigate the interplay between childhood traumatic experiences, hopelessness, depressive symptoms and mental pain, using a network analysis approach in a large transdiagnostic sample of participants living in the community.
Methods: The present investigation was conducted using data gathered in a multicentric observational cross-section study organized as a joint project, including different Italian research and clinical settings. Considering the assessment tools adopted in the study, 12 different variables were included as nodes in the EBICglasso network analysis. Stability of the edges and of centrality indices were assessed using bootstrap procedures, considering case-dropping and node-dropping procedures.
Results: A total of 2147 participants were included in the analysis. Mental pain represents a central feature in a complex network of relationships, including traumatic experiences, hopelessness, and depressive symptoms. More in deatail, mental pain and, to a lesser extent, affective and cognitive depressive symptoms emerged as the most central and influential nodes of the network, highlighting the strong link existing between these aspects and their importance in the lives of people with mental disorders.
Conclusions: Results confirm the importance of mental pain as a transdiagnostic feature, requiring careful assessment and consideration in all patients, beyond the diagnostic categories and regardless of suicide risk. Assessing and managing the presence and severity of mental pain should be taken into account in clinical practice, in the perspective of providing significant clinical benefits, as well as relevant research insight
Exploring Traffic Paradoxes: A Study of Roundabout Corridors and Their Effects on Network Dynamics
No full textThis research is part of a broader investigation into dynamic simulation-based approaches for enhancing traffic efficiency, road safety, and sustainability in roundabout corridors and/or road corridors in general. The study emphasizes the need to analyze road intersections as interconnected systems rather than isolated components, aiming to better understand and mitigate counterintuitive phenomena known as traffic paradoxes, including the well-known Braess Paradox. The first section introduces the main traffic paradoxes, exploring their definitions, real-world implications, and reproducibility in roundabout corridors. The second section focuses on a case study of the “SS1—Via Aurelia Nord” in Pisa (Italy), where converting a traffic-light-controlled corridor into a roundabout corridor unexpectedly led to increased congestion. This paradoxical outcome is analyzed within the broader context of network dynamics and sustainable mobility planning. Dynamic simulations were performed using Aimsun software, and a novel performance index—the “Celerity Roundabout Corridors” (CRC)—was proposed to quantify and detect these paradoxical effects. The findings highlight conditions under which roundabout corridors may generate inefficiencies despite infrastructural upgrades, emphasizing the importance of systemic, simulation-based evaluations for the sustainable design and optimization of urban traffic networks