Stability Parameters Research Articles

Repolarization dynamics stability in Brugada type-1 pattern subjects with positive and negative genetics

Abstract Background Brugada type-1 pattern (Brgd1) risk stratification in asymptomatic subjects and its repolarization dynamics are complex. Purpose This study aims to analyze, from alternative standpoints, superficial 12-lead ECG V1 repolarization patterns (repol.). This method diverges from standard ECG pattern characterization. It rather exploits nonlinear dynamics and stability of ECG repol. to assess stability driving cardiac dynamics. This work consists in analyzing 2 subjects with Brgd1: Subject1 with negative genetics and negative EP study. Subect2 with positive genetics. Target To deepen knowledge/insight and applications of control-and-stability-theory applied to 12-lead ECG, aiming to eventually diminish the number of invasive EP studies. Methods A stability control closed loop system has been designed to model electrophysiology dynamics of cardiac conduction: ECG segments being the input-output of the system. (Figure). A sequence of V1 repol. have been scanned, digitized, and quantitatively processed yielding stability parameters (poles in S-plane). Scanning and signal processing performed by Matlab R_2023b. Results Figures. Conclusions Based on our data, 12-lead-ECG repol. seem to be associated with increasing stability in Subject1, exhibiting negative genetics. On the other hand, less stability seems to be associated with Subject2, reporting positive genetic tests. In conclusion, furthering control-and-stability-theory applied to 12-lead ECGs aims to deeper comprehension of physiological and pathological substrates of malignant arrhythmias, and to focus on noninvasive risk stratification strategies for ICD implantation indication in BrS. Further development of this technique will be largely facilitated by the implementation of AI methodologies in the near future.

Parameters of Water Column Stability in a Small Polymictic Lake in Years of Different Weather Conditions

Parameters of Water Column Stability in a Small Polymictic Lake in Years of Different Weather Conditions

#3038 Plasma exchange for refractory IgA Vasculitis

Abstract Background and Aims IgA Vasculitis (IgAV) frequently has a relapsing/refractory course despite glucocorticoids and immunosuppressive therapies and the management of severe disease remains controversial [1]. Plasma exchange (PLEX) has been used as a rescue treatment in other vasculitides, particularly in cases with rapidly progressive glomerulonephritis, but little is known about its role in IgAV. Here we present outcomes of patients with refractory IgAV treated with PLEX at our centre. Method Clinical records of patients who met 1990 American College of Rheumatology classification criteria and 2012 Chapel Hill Consensus Conference definitions for IgAV were analysed and those receiving ≥1 course of PLEX (5 sessions) identified from our PLEX database. We assessed demographic and clinical features at diagnosis and at starting of PLEX. Response was defined as an improvement in vasculitis activity measured with Birmingham Vasculitis Activity Score (BVAS) 1 month after PLEX course completion and classified as “partial” (BVAS<3 and prednisolone <10 mg/day) or “complete” (BVAS = 0). Both definitions included changes in eGFR and proteinuria. Relapse was defined as an increase in BVAS after initial response. Early adverse events occurring during PLEX course or within one week after completion of this were recorded. Results Among 174 patients with IgAV, 12 (7%) received ≥1 course of PLEX. This was started a median of 15 months after diagnosis (interquartile range, IQR 3-40). All patients received glucocorticoids and immunosuppressive therapy prior to PLEX (Table). At the time of starting PLEX, 8/12 patients had active skin involvement (7/8 had purpura and 2/8 ulcers) and 10/12 nephritis, with a median eGFR 34 mL/min (IQR 30-43) and a median urine albumin:creatinine ratio (UACR) of 298 mg/mmol (IQR 240-486). PLEX was combined with glucocorticoids and various immunosuppressive agents, most commonly cyclophosphamide (42%) or mycophenolate mofetil (33%). All but one patient had a response at 1 month, and this was “complete” in five (42%). The median eGFR of patients with active nephritis increased up to 44 mL/min/1.73 m2 (IQR 36-58) and the median UACR drop to 182 (IQR 159-408). Ten patients (91%) relapsed a median of 3 months (IQR 2-7) after completion of the PLEX course and 8/10 (80%) resumed PLEX and achieved response. Six patients (50%) continued a “chronic” regimen of PLEX (1-2 monthly sessions) for a median of 85 months (25-141), as this was the only therapy that could control skin (4/6) and/or kidney manifestations (3/6). Three patients experienced infection within a week of PLEX discontinuation and two reported reactions to FFP/albumin, but all recovered completely. Three patients (25%) developed kidney failure during follow-up and two died (one of whom had kidney failure), with death occurring 9 and 146 months after discontinuation of PLEX. Conclusion In this small cohort of adult patients with severe and refractory IgAV, PLEX was associated with improved disease control, stabilisation of renal parameters, and few early adverse events. The clinical response to PLEX appeared temporary, but some patients maintained remission through a “chronic” PLEX regimen. As highlighted by the high risk of death or kidney failure, more effective therapies for IgAV are needed but PLEX should be considered as a rescue treatment in severe/refractory cases.

Magnesium-eutectic electrolyte as a winning combination for sustainable battery

Eutectic-Magnesium electrolytes are sparsely used electrolytes in Magnesium ion batteries. In this context, readily available less toxic precursors based eutectic electrolytes are attracting increasing interest owing to the focus of sustainable battery development. The unique benefits of magnesium such as high specific capacity, low reduction potential, and remarkable reversibility without dendrimer formation are highly advantages when compare to lithium based batteries. Developing an optimal electrolyte composition is a key area of study in the field of battery technology. With improved cell performance, stability across cycles, and general safety, we hope to reduce unwanted interfacial reactions. In this study, we examined eutectic combination of trimethylamine hydrochloride and aluminium chloride (TMA: AlCl3 = TMA) along with magnesium perchlorate to understand ion-solvation, complexation, thermal stability, ion transport and conduction, and electrochemical stability, certain physico-chemical and electrochemical parameters were evaluated prior to assessing the cell's performance. The salient features being an ionic conductivity (σ) of 6.25×10−3 mS cm−1 at 30 °C, remarkable performance retention with over 90 cycles of operation with the electrolyte and an impressive capacity of 90 mAh/g. The behaviour of ionic conductivity with temperature followed the Vogel-Tammann-Fulcher (VTF) equation. Moreover, the anodic stability around 2.5 V (Mg/Mg2+) when platinum is used as the working electrode endorses the suitability of the electrolyte for use in Rechargeable Magnesium Batteries (RMBs).The promising results of this first investigation open up new possibilities for investigating complementary pairings with the aim of improving the efficiency of magnesium-ion cells.

Amplification in parametrically-driven resonators near instability based on Floquet theory and Green’s functions

Here we use Floquet theory to calculate the response of parametrically-driven time-periodic systems near the onset of parametric instability to an added external ac signal or white noise. We provide new estimates, based on the Green’s function method, for the response of the system in the frequency domain. Furthermore, we present novel expressions for the power and noise spectral densities. We validate our theoretical results by comparing our predictions for the specific cases of a single degree of freedom parametric amplifier and of the parametric amplifier coupled to a harmonic resonator with the numerical integration results and with analytical approximate results obtained via the averaging method up to second order.

Development of unique soil organic carbon stability index under influence of integrated nutrient management in four major soil orders of India

Stability of soil organic carbon (SOC) is pre-requisite for stabilization of C leading to long-term C sequestration. However, development of a comprehensive metric of SOC stability is a major challenge. The objectives for the study were to develop novel SOC stability indices by encompassing physical, chemical, and biochemical SOC stability parameters and identifying the most important indicators from a Mollisol, an Inceptisol, a Vertisol, and an Alfisol under long-term manuring and fertilization. The treatments were control, 100%NPK, 50% NPK+ 50% N through either farmyard manure, cereal residue, or green manure. SOC stability indicators were selected, transformed and integrated into unique SOC stability indices via conceptual framework and principal component analysis. Principal component analysis identified Al-macroaggregate, humic acid C-microaggregate, microaggregate-C, particulate organic matter-C-macroaggregate and polyphenol-microaggregate as the important SOC stability indicators. The principal component analysis -based SOC stability index varied from 0.2 to 0.9, 0.1 to 0.5, 0.2 to 0.6, 0.1 to 0.5 for Mollisol, Inceptisol, Vertisol and Alfisol, respectively. The SOC-stability index derived from conceptual framework and principal component analysis significantly lined up well with one another, although NaOCl-Res-C showed a high correlation with both conceptual framework (r = 0.8) and principal component analysis-based (r = 0.7) SOC stability indexes, suggesting that both methods might be used to quickly assess SOC stability in four soil orders. Overall, 50%NPK+50%N by farmyard manure or green manure emerged as the most effective management practices for enhancing stability of SOC in Mollisol, Inceptisol, Vertisol, and Alfisol of India which might act as major C sink in rice-wheat and maize-wheat cropping systems. The other aspect of C sequestration is to enhance agricultural productivity without depending much on expensive chemical fertilizers. The model yardstick thus developed for assessing SOC stability might be useful to other systems as well.

Systematic Control Design for Adaptive Rejection of Narrow-Band Disturbances Based on a Novel Resonant Generalized Extended State Observer

In this paper, the adaptive rejection of multiple narrow-band disturbances with time-varying frequencies is investigated. A systematic control approach based on a resonant generalized extended state observer (RGESO) is proposed. The frequency response of the RGESO is shaped into a desired form to reject the total disturbance, including the wide-band uncertainties and the narrow-band disturbances. The state-space realization of the RGESO is also provided to estimate both the states and the total disturbance. To handle the time-varying frequencies of the narrow-band disturbances, a direct frequency estimation approach based on the Levenberg–Marquardt method and an online supervision strategy is presented to improve convergence and reliability, and the estimations are then used to adapt the RGESO parameters. Parameter tuning and stability robustness analysis methods are also developed for the proposed scheme to facilitate its application. Finally, extensive simulations are conducted to demonstrate the effectiveness of our method.

Experimental Study of a Novel Helix-Shaped Oscillating Heat Pipe and Design Parameters for Flow Stabilization

Abstract Abstract A novel helix-shaped oscillating heat pipe (OHP) designed for enhanced heat transfer in thermal management and heat recovery was studied experimentally. Two orientations were explored: side-heated, the intended orientation in which improved fluid circulation is expected, and bottom-heated, a control resembling traditional bottom-heated OHPs. Results showed stronger circulation, reduced temperature differences, and lower start-up thresholds in most side-heated cases. This orientation achieved higher maximum heat loads at a fill ratio of 0.5, although the maximum heat load decreased at a fill ratio of 0.7. Notably, the experimental OHP attained an effective thermal conductivity over 9,000 W m-K-1 in multiple tests and a maximum heat transport of 676 W. Additional parameters were explored including heat load, fill ratio, condenser temperature, and the presence of noncondensable gases (NCGs). NCGs increased the temperature drop as expected, but also raised the maximum heat transport, indicating potential benefits in certain applications. Elevated condenser temperatures decreased temperature drops, but also reduced maximum heat transport. A previously developed OHP performance model was expanded to evaluate the novel helix-shaped OHP. The model reasonably predicted temperature drops during degassed experiments under moderate heat loads. However, most data points fell outside the model's scope, emphasizing the need to extend it to handle condenser bubble collapse. The expanded analytical models for side-heated helix OHPs highlighted restrictions on circulation that differed from traditional, bottom-heated OHPs, which explains the superior performance of the novel design.

A novel coordinate transformation stability criterion and parameter selection for grid-connected inverter

The negative resistance of grid-connected inverter (GCI) and the increasing number of GCI in power grid pose great challenges to the stability of GCI. This paper proposes a coordinate transformation stability criterion (CTSC) based on the single-input single-output (SISO) impedance model for GCI system. A low complexity fractional polynomial model of GCI is derived by the Pade approximation and the SISO impedance model in the αβ domain. CTSC is proposed by applying the Nyquist stability criterion, which simplifies the graph trajectory criterion to a numerical criterion. Since the effect of parameter on stability is usually limited to the neighborhood, average parameter assessment metric (APAM) is proposed based on CTSC to evaluate the impact of each parameter over a wide range. Additionally, joint parameter assessment metric (JPAM) is proposed to simultaneously adjust multiple parameters on stability. Finally, compared with the three criteria for conservatism analysis, CTSC possesses the lowest conservatism. The theory proposed in this paper is verified by experiment.

ANALYZING DEVICES AND METHODS FOR ASSESSING THE PRIMARY STABILITY OF ORTHODONTIC MINI-IMPLANTS

When disruptions occur in the mechanisms regulating the eruption of lower jaw molars, it becomes necessary to artificially extract and reposition them within the dentition. Various treatment methods are employed for this purpose, with the primary approach involving traction fixed to teeth or other anchorage elements and bone supports. Skeletal support is preferred to minimize resistance from orthodontic appliances when applying force to the patient's teeth. The utilization of mini-implants for anchorage demonstrates a relatively high success rate, though instances of failures and complications are not unheard of. Potential issues such as stability loss and mini-implant displacement may necessitate relocation or adjustments to treatment strategies, posing challenges for both practitioners and patients. Unlike dental implants, where secondary stability often dictates treatment success, primary stability holds paramount importance for orthodontic mini-implants. Investigating primary stability parameters can significantly impact treatment strategy selection and orthodontic mini-implant loading timelines. Focusing solely on mini-implant torque during placement is inadequate, as it fails to comprehensively gauge real stability. Moreover, the available range of torque indicators for orthodontic mini-implant placement is limited, typically ranging from 5ncm to 10 ncm. Furthermore, the selection of specialized devices for measuring primary stability is limited and necessitates meticulous evaluation.

Evaluation of the colour stability of different ceramic materials with two thicknesses

Society places a great emphasis on aesthetics, & there is a constant rise in the demands placed on dental restorations' aesthetics. The aim of this in-vitro research was to study the impact of the finishing protocol on the color stability parameter of different glass-ceramic materials with two different thicknesses, before & after thermocyling. One hundred twelve specimens had been prepared with standard dimensions of one mm & two mm thickness & ten mm diameter for the four different glass-ceramic materials. The ceramic specimens had been separated into 4groups according to ceramic material (n=28): IPS e.max Press, CeraMotion, Rosetta SP & CeltraPress, each group had been subdivided into two sub-groups according to the specimen thickness (n=14): 1 mm and 2 mm. Each sub-group was further split into 2 divisions according to the finishing protocol (n=7): glazed only & polished then glazed. The results of our study all samples have shown color change within visually perceptible but clinically acceptable level (more than 1 and less than 3.7), emax glazed samples (1mm&2mm) together with emax glazed and polished samples (1mm) have shown significantly higher ΔE beyond the clinically acceptable level. Increasing ceramic thickness from 1 mm to 2 mm has shown better color stability in Emax group. Polishing before glazing increased color stability in Emax while decreased it in Celtra.

Genotype-by-environment interaction analysis for grain yield of barley genotypes in the warm climate of Iran

In the present study, multi-environmental trials were performed on 19 newly developed barley genotypes at five test regions across the warm climate in Iran for two consecutive years. The results of additive main effects and multiplicative interaction (AMMI), GGE biplot (GGE) model, and several BLUP-based stability parameters and integrated models (WAASB and WAASBY) were used to reveal GEI patterns and identify superior genotypes with stable grain yield across test environments. Statistical analyses revealed that grain yield was influenced by significant environments (E), genotypes (G), and GEI effects. Among AMMI-, BLUP-, and grain mean-based stability parameters, the harmonic means of genotypic values (HMGV), relative performance of genotypic value (RPGV), and harmonic mean of RPGV parameters indicated a dynamic concept of stability. Moreover, results of GGE biplot analysis identified three mega-environments with different winner genotypes in test environments. Regardless of the different years, the Ahvaz, Darab, and Moghan regions were identified as Type-II environments due to their highest discrimination power and representative ability. The grouping pattern considerably followed the ranking of genotypes in GGE biplot analysis and WAASB model. In conclusion, our results revealed that genotypes G9 and G10 had grain yield higher than the reference genotype and relative stability in specific environments with favorable environmental conditions. Genotype G5 had general adaptability and stability across all test environments. This genotype can be recommended for cultivation in a wide range of environments in the warm climate of Iran.

Ablate and pace with conduction system pacing, Rovigo's experience

Abstract Background Several clinical data demonstrate that atrio ventricular junction (AVJ) ablation, followed by cardiac pacing, in atrial fibrillation (AF) with uncontrollable heart rate is beneficial. There are still limited data about conduction system pacing (CSP) in that setting. Aims To analyse if this “ablate and pace” strategy is feasible with good electrical results (ECG and parameters) and clinical outcomes (heart failure (HF) admission, ejection fraction (EF) and NYHA class). To analyse also differences between his bundle pacing (HBP) and left bundle branch area pacing (LBBAP) in this setting. Methods. This is an observational retrospective single center study involving 30 patients of which 11 had a HBP and 19 a LBBAP from March 2019 to June 2023 (medium follow up 33 ± 18 month). The implant procedure was performed with both stylet driven or lumenless lead. After 2 ± 2 weeks was performed the AVJ ablation. The electrical parameters were measured at the implant and every 6 – 12 months. The patients had an echocardiographic and clinical evaluation every 6 – 12 months. There was nobody with a NYHA class IV. Results The procedure was performed without complication in all patients. There were a rising in the EF (49,9 ± 14,6 vs 54,2 ± 10,4% p = 0.004). There weren’t HF admission and only 2 patients died (not for cardio–vascular causes) during follow up. There were also a decrease in NYHA class in every patient (at least one NYHA class less). 17 (57%) patients had normal ventricular conduction, only 4 (13%) had LBBB, 4 (13%) RBBB. There were not statistical difference between the QRS duration pre and after implant (129 ± 35 vs 125 ± 24 ms p = 0,06). The threshold measured at the implant were stable both in the HBP (0,75 ± 0,34 vs 1,3 ± 0,8 V @ 0,4 ms p = 0,14) and in the LBBAP (0,93 ± 0,3 vs 0,89 ± 0,3 V @ 0,4 ms p = 0,49). The LBBAP presented higher values of sensing compared with HBP (17,5 ± 7,4 vs 6,3 ± 3,3 mV p = 0,04) and less procedural (63 ± 32 vs 95 ± 41 min, p = 0,02) and fluoroscopic time (2,6 ± 2,4 vs 7,5 ± 4,1 min, p = 0,04) compared with HBP. Conclusion The CSP is feasible and safe in the setting of “ablate and pace” and results in a clear increasing in EF and clinical status of patients with good and stable ECG features and electrical parameters during follow up; the CSP indeed represent a valuable alternative to BVP in this setting. LBBAP performed better than HBP in terms of procedural and fluoroscopic time and of higher sensing values.

Stability Analysis and Genetic Variability in Buckwheat (Fagopyrum esculentum Moench.)

Aims: To estimate the genetic variability and to identify the stable buckwheat genotype for growth and yield parameters. Study Design: Eberhart and Russell model. Place and Duration of Study: Department of Plantation, Spices, Medicinal and Aromatic Crops, College of Horticulture, Bagalkot, Karnataka during Jan-April 2021-2022. Methodology: Fifteen genotypes of buckwheat were assessed for stability parameters for 15 characters across three environments i.e, full dose of recommended fertilizer (RDF), 3/4th dose of RDF and 1/2nd dose of RDF. The pooled data of these environments were used for estimation of genetic variability. Results: The heritability estimates were moderate to high for all the characters. The genetic advance over mean was found highest for number of clusters per cyme (35.05%), seed yield per plot (32.68%) and seed yield per hectare (32.72%). The genotype EC-104035 was found stable for seed yield per plant, per plot and hectare, EC-386667, EC-3222, Nilgiri local, PRB-1 and Sangla B-460 for thousand seed weight, IC-313134 and EC-3222 for plant height at 45 days after sowing and at harvest, Shimla B-1 for plant height at 15 days after sowing, IC-49671, IC-274429 and Sangla B-460 for number of branches at 30 DAS, PRB-1 for days to first flowering and Nilgiri local for days to 50 percent flowering. Conclusion: The genotypes stable for more traits with high genetic variability, will be considered for future breeding program.

One-dimensional photonic crystals based on porous anodic alumina: Optical and morphology changes under thermal and chemical treatments

One-dimensional photonic crystals (1D PCs) based on porous anodic aluminium oxide (AAO) are promising for light manipulation and sensing. As-prepared AAO, being amorphous material, suffers degradation in acidic and alkaline media. It is commonly known that the chemical stability of AAO increases drastically after thermal treatment. Here, the effect of annealing up to 1200 °C on the morphology and the optical properties of AAO PCs is studied. The two-step crystallization of as-prepared AAO at 860 and 1190 °C leads to a two-step blue shift of the central wavelength of photonic band gap (PBG) and the decrease in PBG depth, whereas the Q-factor of the PBG enhances. The observed changes in optical transmittance spectra of PCs are mainly attributed to the increase in pore diameter, the formation of crystalline particles of alumina polymorphs, and the removal of impurities. Annealed AAO PCs demonstrate much higher stability of optical parameters during exposure in acidic media compared to the as-prepared ones. Thermal treatment at 600 °C results in 30% decrease in the rate of the PBG shift during chemical etching. Furthermore, AAO crystallization into a mixture of low-temperature alumina polymorphs at 860 °C leads in a negligible change in transmittance spectra even after chemical etching in 1 M HCl for 75 h. The excellent stability achieved for the annealed AAO PCs in aggressive media proves the perspectives of their application as the optical sensors with long-term stability.

Comprehensive theoretical investigation of NaAlX (X=C, Si and Ge) half-Heusler compounds: Unveiling the multifaceted properties for advanced applications

In this work, we have extensively investigated the characteristics of ternary half-Heusler (HH) materials, specifically NaAlX (X[Formula: see text][Formula: see text][Formula: see text]C, Si and Ge), employing ab-initio computations in density functional theory (DFT) framework. Various aspects, including stability parameters, electronic, optical and thermoelectric (TE) parameters have been examined. The computed lattice constants of NaAlX (X[Formula: see text][Formula: see text][Formula: see text]C, Si and Ge) were found to be, respectively, 5.398, 6.301 and 6.389[Formula: see text]Å which are in excellent agreement with the previously available data. The electronic band structures showed that the studied materials exhibit semiconducting behavior with a corresponding band gap of 1.961, 0.999 and 0.846[Formula: see text]eV, respectively. Specifically, NaAlC and NaAlGe compounds were found to have a direct energy band gap at the [Formula: see text]-point, while NaAlSi displayed an indirect band gap at the [Formula: see text]–X point. Elastic and thermodynamic parameters were examined, confirming that the titled compounds possess mechanical, dynamic and thermal stability. Additionally, the optical response of the materials has been analyzed within an energy range of 0–13[Formula: see text]eV. The TE parameters exhibited maximum ZT values of 0.998, 0.992 and 0.990 for NaAlX (X[Formula: see text][Formula: see text][Formula: see text]C, Si and Ge) materials, respectively, at 300[Formula: see text]K, suggesting promising TE performance at room temperature.

Effect of Bleaching on Surface Roughness and Color Parameters of Coffee-Stained Nanohybrid Dental Composites with Different Viscosities

Abstract Objective The aim of this study was to test the effect of different bleaching protocols on surface roughness, color stability, and translucency parameter of coffee-stained nanohybrid dental composites with different viscosities. Materials and Methods Five nanohybrid dental composites with different viscosities (n = 250)—Neo Spectra LV, Neo Spectra HV, Neo Spectra Flow (Dentsply, Konstanz, Germany), Grandio, and Grandio Flow (Voco, Cuxhaven, Germany)—were used to test surface roughness, color stability, and translucency parameter after bleaching of coffee-stained specimens using either in-office bleaching, home bleaching, or a combination of both. The viscosity of the five types of dental composites was tested using a viscometer. A scanning laser microscope (SLM) was used to examine the surface topography of representative samples from each dental composite after the combined effect of both bleaching agents. Effect of composite type, bleaching protocol, and their interaction was assessed by two-way analysis of variance. For multiple comparisons, Tukey's post hoc test was used with Bonferroni correction. Results Surface roughness of all coffee-stained dental composites increased after bleaching; however, those of Grandio and Grandio Flow increased significantly (p < 0.0001). This was confirmed by SLM images that showed rough surface with protruding fillers after in-office and home bleaching protocol. Results revealed that bleaching, regardless of the protocol, decreased the delta E values of all dental composites; however, it was still higher than the accepted threshold value of 3.7. Neither of the bleaching protocols enhanced translucency parameter of all dental composites. Neo Spectra Flow and Voco Flow had the highest translucency parameter after the three bleaching protocols. Conclusion Bleaching does not improve color stability and translucency of coffee-stained nanohybrid dental composites regardless of the viscosity. Surface roughness of coffee-stained nanohybrid dental composites increases after application of bleaching agents.

Functional pâté elaborated with tambica (Oligosarcus robustus) and viola (Loricariichythys anus): Oxidative stability, microbiological and sensory quality

The objective of the study was to evaluate the oxidative stability and the microbiological and sensory quality of pâté made from Oligosarcus robustus (tambica) and Loricariichthys anus (viola) fish, containing Lactobacillus acidophilus and fructooligosaccharides, during refrigerated storage. The experiment was entirely randomized, and two formulations of the pâté were subjected to analyses to evaluate oxidative stability, microbiological quality, and microbiological and sensory parameters at 0, 15, 30, 45 and 60 days of storage. In both pâtés, the pH decreased during storage, the count of pathogens, mesophilic aerobes, and psychrotrophic was satisfactory regarding hygienic-sanitary and quality aspects, and Lactobacillus acidophilus remained higher than 9 log CFU g−1. The tambica pâté showed oxidative stability for 60 days, while the viola pâté had a slight variation at 45 days (peroxide index, TBARS, presence of EPA and DHA), which the panelists noticed. Therefore, it is possible to produce a functional fish pâté with oxidative stability and microbiological and sensory quality for a period of 45 days (viola pâté), and extended up to 60 days (tambica pâté) of refrigerated storage.

Interannual Variation in the Zooplankton Community of the North Adriatic Sea under Short-Term Climatic Anomalies

Zooplankton are a pivotal component of the pelagic community, and their abundance and distribution are often strongly dependent on environmental conditions at sea. However, climate change can pose significant challenges to planktonic organisms. Therefore, in this study, we tried to address the possible effect of short-term climatic anomalies on the zooplankton community in the North Adriatic Sea, comparing mesozooplankton composition in June between two years with very different temperature and rainfall levels, i.e., 2019 and 2022. Environmental conditions at sea were significantly different, since 2022 faced rising temperatures in the northern part of the area and higher salinity and lower chlorophyll values in coastal samples. Our data unveiled a community shift, from a Noctiluca-dominated community to a crustacean-dominated one, and revealed that even offshore areas can be subject to changes, despite having quite stable environmental parameters. Our findings confirmed the influence of river inputs and temperature on the Adriatic community’s distribution and composition, highlighting how climate-driven changes could have unpredictable effects on the whole Adriatic ecosystem. Indeed, each species has its own role in ecosystem functioning and climatic anomalies could uncouple the fine-scale connections that make up the pelagic trophic web.

Experimental observation of topological transition in linear and nonlinear parametric oscillators.

Parametric oscillators are examples of externally driven systems that can exhibit two stable states with opposite phase depending on the initial conditions. In this work, we propose to study what happens when the external forcing is perturbed by a continuously parametrized defect. Initially in one of its stable states, the oscillator will be perturbed by the defect and finally reach another stable state, which can be its initial one or the other one. For some critical value of the defect parameter, the final state changes abruptly. We theoretically and experimentally investigate such transition both in the linear and nonlinear cases, and the effect of nonlinearities is discussed. A topological interpretation in terms of winding number is proposed, and we show that winding changes correspond to singularities in the temporal dynamics. An experimental observation of such transition is performed using parametric Faraday instability at the surface of a vibrated fluid.