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DHEA and Cortisol in Rainbow Trout (Oncorhynchus mykiss): Effect of Sex, Sexual Maturity, and Acute Stress Exposure
No full textGlucocorticoids like cortisol are widely used to assess stress in fish, but their interpre-
tation can be limited. Incorporating dehydroepiandrosterone (DHEA), a hormone with
anti-glucocorticoid and neuroprotective effects, may provide a broader understanding of
hypothalamic–pituitary–inter-renal (HPI) axis activity. As DHEA data in fish remain scarce,
this study examined its role in rainbow trout (Oncorhynchus mykiss) subjected to acute
stress (30 min confinement), considering sex and sexual maturity. Cortisol and DHEA were
quantified by optimized radioimmunoassay (RIA) in serum, muscle, fin, and scales, and
gonadal histology was performed to confirm reproductive status. Both hormones were
successfully measured in all matrices, with serum DHEA levels notably higher than those
reported to date in fish. As expected, serum cortisol increased markedly after stress and
correlated with levels in muscle and fin but not in scales, which appears to reflect chronic
rather than acute exposure. In contrast, serum DHEA showed no stress-induced changes
and only minor sex- and maturity-related differences, although alternative matrices dis-
played variable patterns, particularly in muscle and fin. The cortisol/DHEA ratio in serum
mirrored cortisol dynamics, suggesting limited utility for acute stress assessment, while
tissue-specific DHEA variation may integrate longer-term influences. Further research
is needed to clarify the role of DHEA under chronic stress and its potential origins in
inter-renal tissue, gonads, or the brain
Spin-decoupled metasurfaces for the generation of self-accelerating vector beams
No full textThe ability to generate structured light with arbitrary controlled polarization in a compact optical path has been challenging for the last few years in the optics and photonics fields. In this regard, for the first time in our knowledge, this work proposes the design, fabrication, and characterization of spin-decoupled metasurfaces able to generate self-accelerating orbital angular momentum beams having variant topological charges. Illuminated such metasurfaces with a linearly polarized light we are able to generate vector beams and, depending on the polarization angle it is possible to explore different states of the Hybrid Poincaré Sphere (HPS). Our metaoptics are designed as an array of periodic subwavelength metastructures (the so-called meta-atoms) composed of silicon nanofins on a silicon substrate. Each meta-atom acts like a half-wave plate that exploits both the geometrical and dynamical phases in a different way depending on its position on the entire optical element. This design solution offers both compactness of the optical path and easy integration with other optical elements. In particular, the proposed metaoptics are suitable for telecommunications, imaging, particle manipulation, and quantum applications
ADDITIVE MANUFACTURING OF COPPER AND COPPER ALLOYS FOR HIGH ENERGY APPLICATIONS
No full textIn this research activity, the additive manufacturing technology called Laser Powder Bed Fusion (LPBF) was employed to assess the processability of a copper-based alloy and pure copper powders to create components for nuclear fusion reactors. In particular, the research aimed to characterize the materials for building the accelerating grids for a Neutral Beam Injector (NBI) of a tokamak. Since the printing of pure copper is still challenging, the copper alloy has been preferred and investigated more in detail. The CuCrZr alloy was chosen for the study since its composition makes it suitable for its application in nuclear fusion. Additionally, the alloy is mechanically superior to pure copper, and many suppliers can produce the material.
The study began with optimizing the printing process, seeking the most appropriate parameters to provide the lowest porosity in the built parts. Then several heat treatments were performed on the CuCrZr alloy to enhance the material’s performance, either in terms of mechanical properties or thermal and electrical conductivity.
Two machines were employed: the EOSint M280 was initially used, provided with a low-power IR laser (400 W of nominal power), and then the research moved to the AMCM EOS M290, with a 1 kW IR laser of the same wavelength.
From the study, only a laser power above 500 W can successfully print the CuCrZr alloy to obtain parts without defects. However, after the process optimization, the porosity inside the pure copper parts was still 10 times higher than in the CuCrZr material (0.222 % and 0.028%, respectively).
The alloy was revealed to be promising since the heat-treated material reached conductivities equivalent to the as-manufactured pure copper, keeping the mechanical properties higher than the pure copper ones.
The study proceeded with optimizing the surface of the as-built samples, to obtain the best surface finish in the case of inclined surfaces or internal cooling channels that cannot be inspected otherwise.
The analyses carried out during the research were several, such as the microstructure observations with optical and electron microscopy. The investigations of some samples with a Transmission Electron Microscope (TEM) were also carried out, to understand the precipitation mechanism of the alloying elements inside the CuCrZr alloy after the heat treatments.
Subsequently, hardness was measured and, in some cases, microhardness was investigated, too, both in as-built conditions and after treatments for CuCrZr and pure copper. Electrical conductivity was assessed through eddy current measurements, and other tests were carried out to complete the characterization, such as tensile tests, thermal conductivity measurements, Differential Scanning Calorimetry (DSC), and X-Ray Diffraction (XRD). The thermal conductivity was measured through an in-house-made setup developed at the University of Padova to recreate a 1-D steady-state thermal flow
Riforma della cittadinanza iure sanguinis: diritto comparato e tutela multilivello
No full textThe paper reconstructs the distinctive features of the Italian iure sanguinis citizenship model and the emerging demands for reform, and critically
reviews the most recent legislative developments. It highlights the significant differences with other major European legal frameworks, as well as potential issues of unconstitutionality and violations of EU law in light of the most recent case law. Finally, it outlines an analysis of the compensability of damages resulting from unlawful legislative acts, within a multi-level protection framework
Abnormal Glucagon Secretion Contributes to a Longitudinal Decline in Glucose Tolerance
No full textContext Defects in insulin secretion and action contribute to the progression of prediabetes to diabetes. However, the contribution of α-cell dysfunction to this process has been unclear. Objective This work aimed to understand the relative contributions of α-cell and β-cell dysfunction to declining glucose tolerance. Methods A longitudinal, community-based observational study was conducted at a clinical research unit at an academic medical center. We studied 96 individuals without diabetes (age 55 ± 1 years; body mass index 27.7 ± 0.4) on 2 occasions, 3 years apart using an oral 75-g glucose challenge. Indices for insulin secretion and action were estimated using the oral minimal model. Glucagon secretion rate (GSR) was estimated by deconvolution from peripheral glucagon concentrations. Main outcome measures included glucose tolerance status (categorical variable) and then symmetrical percentage change in peak and 120-minute glucose (post oral glucose tolerance test) concentrations (continuous variables). Results A total of 32 individuals progressed from normal to impaired glucose tolerance (IGT) or from IGT to type 2 diabetes. The disposition index (DI) declined in the progressors (568 ± 98 vs 403 ± 65 10-4 dL/kg/min per μU/mL, baseline vs 3 years; P =. 04). α-Cell suppression by glucose (δGSR/δglucose) did not change in the nonprogressors (1.5 ± 0.1 vs 1.3 ± 0.1 nmol/min/L; P =. 37) but decreased (1.0 ± 0.2 vs 0.8 ± 0.2 nmol/min/L; P <. 01) in those who progressed. Analysis of the entire cohort showed that DI and δGSR/δglucose were independently and inversely correlated with an increase in glycemic excursion. Conclusion These data show that α-cell dysfunction accompanies a decline in β-cell function as IGT or overt type 2 diabetes develops
Lo spazio europeo dei dati sanitari. Prime riflessioni sul Regolamento UE 2025/327
No full textIl reg. UE 2025/327 istituisce lo spazio europeo dei dati sanitari (c.d. EHDS), il primo spazio europeo comune di dati. Pietra miliare dell’Unione europea della salute e tappa fondamentale della strategia europea dei dati, il regolamento disciplina il trattamento di dati sanitari elettronici per l’uso primario e l’uso secondario. Tra i profili cruciali del regolamento, particolare attenzione meritano la definizione di dati sanitari elettronici, il rapporto con la protezione dei dati personali, il diritto di esclusione e l’apparato rimediale. Dinanzi alle svariate questioni che esso lascia aperte, preminente sarà il ruolo dell’interpretazione del diritto.
Regulation EU 2025/327 establishes the European Health Data Space (EHDS), the first common European data space. A milestone of the European Health Union and a landmark in the European data strategy, the regulation disciplines the processing of electronic health data for primary and secondary use. Among the crucial profiles of the regulation, particular attention should be paid to the definition of electronic health data, the relationship with personal data protection, the right to opt out and the remedies framework. Faced with the many questions it leaves open, the role of legal interpretation will be paramount
Manuale di diritto privato Torrente Schlesinger Anelli - Aggiornamento-revisione
No full textSi tratta della revisione e aggiornamento di un Manuale storico della materia, connotato da una specifica attenzione all'interpretazione giurisprudenzial
Effect of cultivar differences in seed size on early season growth and physiology of cotton under low and high‐temperature extremes
Get PDFExtreme temperatures and cultivar variation in seed characteristics affect stand
establishment, early-season growth, and photosynthetic processes. However, studies
addressing temperature responses of similarly adapted cultivars of contrasting seed
traits are needed. This study assessed the effect of temperature and cultivar on growth,
physiological responses, and photosynthetic thermotolerance in cotton (Gossypium
hirsutum L.) seedlings and identified important plant traits contributing to seedling
vigor. Two similarly adapted cotton cultivars with contrasting seed sizes were grown
in a controlled environment under 4 day/night temperature regimes, 20/15, 30/20,
35/25, and 40/30°C, for 4 weeks. Growth analysis, chlorophyll fluorescence, and gas
exchange data were collected. Rapid induction fluorescence × incubation temperature
experiments were used to define temperature thresholds, causing a 15% decline
in photosynthetic efficiencies (T15). The large-seeded cotton cultivar exhibited higher
values for most growth traits. The 20/15°C temperature had the lowest values for all
growth traits, and 30/20 and 35/25°C were optimal for shoot growth. Leaf area was
the most important driver of seedling vigor, and whole-canopy photosynthesis could
be a more accurate predictor of biomass accumulation than net carbon assimilation
per unit leaf area. Plants grown at 20/15°C had the lowest net carbon assimilation
rates, primarily due to metabolic impairment. Photosystem I (PSI) and photosystem
II (PSII) had greater heat tolerance than inter-photosystem electron transport.
The thermotolerance of all thylakoid responses increased as the early-season growth
temperature increased, and there were cultivar differences in acclimation potential
for PSI
The impact of age and frailty on hospitalization and survival in older liver transplant recipients: a longitudinal cohort study
Get PDFPurpose: Frailty is a well-established risk factor for adverse outcomes, particularly in liver transplant candidates. This study investigates the impact of age and frailty on key clinical outcomes—hospitalizations, waitlist survival, and post-transplant mortality—in cirrhotic patients evaluated for liver transplantation. Methods: This study included older adults with chronic liver disease under consideration for transplantation. Data collected encompassed medical history, Model for End-Stage Liver Disease (MELD) and Child-Turcotte-Pugh (CTP) scores, Mini-Mental State Examination (MMSE), Mini Nutritional Assessment (MNA), and frailty status, assessed using both the Liver Frailty Index (LFI) and the Survey of Health, Ageing, and Retirement in Europe Frailty Index (SHARE-FI). Clinical outcomes, including mortality and hospitalizations, were tracked over a 24-month period. Results: Among 100 patients (67% male), those under 70 exhibited higher MNA, MMSE, and SHARE-FI scores. Based on frailty classification, 25 patients were frail, 28 pre-frail, and 47 robust. Younger patients experienced more hospitalizations during follow-up (p = 0.03) and had a higher probability of hospitalization within 24 months (p = 0.002). Although transplant-free survival did not differ significantly across groups, frail patients had a significantly higher mortality rate (p = 0.04). Overall, 24 patients underwent transplantation, while 26 died, including six post-transplant deaths. MELD and CTP scores were strong predictors of mortality, while among frailty measures, only SHARE-FI demonstrated significant predictive value. In multivariate Cox models, MELD [HR = 1.17, p = 0.001; HR = 1.11, p = 0.002], CTP [HR = 1.43, p = 0.003; HR = 1.41, p = 0.006], and LFI (HR = 1.69, p = 0.04) were significantly associated with mortality. Conclusion: Frailty, rather than age, emerges as a key predictor of mortality in liver transplant candidates. Further research is needed to validate these findings and enhance frailty assessment, ultimately improving candidate selection for transplantation
Bioelectrical impedance vector analysis in older adults: reference standards from a cross-sectional study
Get PDFBackground and Aims: The bioelectrical impedance vector analysis (BIVA) requires population-specific references to correctly classify individuals based on body composition properties. The aim of this study was: (i) to develop new references specific to the older adult population; (ii) to evaluate vector patterns based on age and appendicular lean soft mass (ALMS); (iii) to compare the new references with others already existing in the literature. Methods: The present study included 835 older adults [472 women (mean age 73.9 ± 7.4 years, BMI 27.2 ± 5.4 kg/m2) and 363 men (mean age 73.1 ± 7.2 years, BMI 27.0 ± 4.4 kg/m2)]. Bioimpedance analysis was conducted using a phase-sensitive foot-to-hand technology at 50 kHz. Bioelectrical properties were analyzed among participants grouped by age categories and ALSM tertiles. New bivariate tolerance ellipses for resistance (R) and reactance (Xc), standardized by participants’ height (H), were compared with data from adult populations and the original BIVA references proposed by Piccoli in 1995 (ages 15–85). Results: New reference values for older adults were established. Significant differences (p < 0.001) in R/H and phase angle were observed when older adults were grouped by age categories, while R/H, Xc/H, and phase angle showed significant differences among ALSM/H2 tertiles. The mean bioelectrical vector for older adults differed from the references in the literature, showing a moderate magnitude relative to Piccoli’s original BIVA references (men: D2 = 0.6; women: D2 = 0.5) and a larger magnitude compared to the adult standards (men: D2 = 1.7; women: D2 = 1.8). Conclusion: This study provides BIVA references for older adults. Aging was associated with increased R/H and decreased phase angle, whereas older individuals with higher ALSM exhibited a greater phase angle and lower R/H, and Xc/H. The original BIVA references proposed in 1995 lack specificity and are no longer recommended for future use, as age-specific bioelectrical references are now available