Note al testo dei Posthomerica di Quinto Smirneo

The paper discusses some problematical passages of Quintus Smyrnaeus’ Posthomerica (1.733, 2.162-3, 3.399-403, 6.323-7, 422-3, 7.474-6, 545-52, 8.336-40), both considering the possibility of defending the transmitted text and suggesting new conjectures

Brassinosteroids interact with nitric oxide in the response of rice root systems to arsenic stress

Brassinosteroids (BRs), an emerging class of phytohormones, affect numerous plant physiological and metabolic processes and can improve plant defense systems to counteract metalloid phytotoxicity. Nitric oxide (NO), a reactive nitrogen species (RNS), behaves as a signalling molecule activating plant cellular responses to various environmental conditions. Brassinosteroids induce NO synthesis through nitrate reductase (NR) and NO synthase (NOS) activities. Arsenite and arsenate, inorganic forms of the metalloid arsenic (As), cause both soil pollution and many disorders in numerous plants, including important crops like rice, due to the oxidative stress generated by the imbalance between RNS and reactive oxygen species (ROS). Rice is very susceptible to As toxicity because both As availability and solubility are high in flooded paddy fields in many cultivated areas. The research aims to investigate the effects of BRs on the rice root systems exposed to 10-4 M Na2HAsO40.7 H2O [As(V)] or 2.5 × 10-5 M NaAsO2 [As(III)], highlighting the induced cyto-histological events and dissecting the NO role in the root response. A specific concentration (10-7 M) of 24-epibrassinolide (24-eBL), an exogenously applied BR, increases lateral root (LR) formation of more than 50% in the presence of As(III) or As(V). In addition, eBL attenuates the thickening of the cell walls induced by As in the outermost root cortical layers of LRs and in the adventitious roots (ARs) by reducing of ⁓ 50% the lignin deposition, while it restores the As(v)-altered NO levels by increasing OsNOS1 expression and the cellular NO distribution

Default and Control Networks Connectivity Dynamics Track the Stream of Affect at Multiple Timescales

In everyday life, the stream of affect results from the interaction between past experiences, expectations and the unfolding of events. How the brain represents the relationship between time and affect has been hardly explored, as it requires modeling the complexity of everyday life in the laboratory setting. Movies condense into hours a multitude of emotional responses, synchronized across subjects and characterized by temporal dynamics alike real-world experiences. Here, we use time-varying intersubject brain synchronization and real-time behavioral reports to test whether connectivity dynamics track changes in affect during movie watching. The results show that polarity and intensity of experiences relate to the connectivity of the default mode and control networks and converge in the right temporoparietal cortex. We validate these results in two experiments including four independent samples, two movies and alternative analysis workflows. Finally, we reveal chronotopic connectivity maps within the temporoparietal and prefrontal cortex, where adjacent areas preferentially encode affect at specific timescales

Body mass index rather than the phenotype impacts precocious ultrasound cardiovascular risk markers in polycystic ovary syndrome

Objective Research into cardiovascular disease (CV) prevention has demonstrated a variety of ultrasound (US) markers predicting risk in the general population but which have been scarcely used for polycystic ovary syndrome (PCOS). Obesity is a major factor contributing to CV disease in the general population, and it is highly prevalent in PCOS. However, it is still unclear how much risk is attributable to hyperandrogenism. This study evaluates the most promising US CV risk markers in PCOS and compares them between different PCOS phenotypes and BMI values. Design Women fulfilling the Rotterdam criteria for PCOS were recruited from our outpatient clinic for this cross-sectional study. Methods Participants (n\u2009=\u2009102) aged 38.9 \ub1 7.4 years were stratified into the four PCOS phenotypes and the three BMI classes (normal-weight, overweight, obese). They were assessed for clinical and biochemical parameters together with the following US markers: coronary intima-media thickness (cIMT), flow-mediated vascular dilation (FMD), nitroglycerine-induced dilation (NTG), and epicardial fat thickness (EFT). Results There was no statistical difference among the four phenotypes in terms of cIMT, FMD, NTG or EFT, however all the US parameters except NTG showed significant differences among the three BMI classes. Adjusting for confounding factors in multiple regression analyses, EFT retained the greatest direct correlation with BMI and cIMT remained directly correlated but to a lesser degree. Conclusions This study showed that obesity rather than the hyperandrogenic phenotype negatively impacts precocious US CV risk markers in PCOS. In addition, EFT showed the strongest association with BMI, highlighting its potential for estimating CV risk in PCOS