Search Results (291)

Olive mill wastewater (OMW) is a phenol-rich effluent with high organic load, posing significant environmental disposal challenges in the Mediterranean countries. This study evaluated the bioremediation and valorization potential of OMW by eleven edible and/or medicinal fungal strains (Agrocybe cylindracea, Lentinula edodes, Pleurotus sapidus, Pleurotus sajor-caju, Flammulina velutipes, Ganoderma adspersum, Tuber aestivum and Tuber mesentericum). Firstly, screening for mycelial growth on agar media with commercial glucose and OMW (concentrations from 0 to 50%, v/v) revealed a strain-specific tolerance to phenolic toxicity. Although all tested strains could grow on OMW-based media, G. adspersum, T. mesentericum and T. aestivum presented the highest mycelial growth rates (Kr), exceeding 10 mm/day at elevated OMW levels (50%, v/v). Based on screening outcomes, seven strains were selected for further evaluation under static liquid fermentations in media with 15 and 35% (v/v) OMW. Growth kinetics, substrate consumption, phenolic removal, decolorization capacity, intracellular polysaccharide (IPS) and total lipid content were assessed. Tuber spp. and G. adspersum exhibited the highest tolerance to phenolic compounds, producing biomass exceeding 15 g/L at 35%, v/v OMW. Maximum IPS production reached up to 46.23% (w/w), while lipid content exceeded 15% (w/w) of dry biomass in F. velutipes and T. mesentericum, indicating an oleaginous microorganism-like behavior. Phenolic removal surpassed 80% in most cases, demonstrating efficient enzymatic degradation. Decolorization efficiency varied between strains, but remained above 70% for L. edodes, G. adspersum and F. velutipes. These findings highlight the potential of edible and/or medicinal fungi to simultaneously detoxify OMW and produce biomass and high-value metabolites, supporting a sustainable, low-cost agro-industrial waste management aligning with circular bioeconomy principles. Full article

Anaerobic digestion piggery effluent (ADPE), dark brown with high turbidity and ammonium, inhibits algal growth and requires pretreatment for cultivation. This study compared various physical/biological pretreatment methods for microalgae cultivation. The results showed that the strategy of 10%ADPE fungal cultivation (10%AF) pretreatment and subsequent microalgae cultivation achieved maximum specific growth rate (0.094 d⁻¹) with productivity (0.014 g L⁻¹ d⁻¹) and significant nutrient removal: 100% ammonium nitrogen, 99% total nitrogen, 63% total phosphorus, 91% chemical oxygen demand. However, the pathogenic fungus used poses safety risks, requiring future screening of eco-friendly alternatives. This study demonstrated that the strategy could be a promising approach to algal biomass production and nutrient removal from ADPE. Full article

Semitransparent plastic films containing red-fluorescent pigments can increase the growth of some greenhouse crops despite a lower transmitted photosynthetic photon flux density (PPFD), but the underlying mechanism by which this occurs is not fully understood. We postulated it can be attributed to a lower blue-light environment that increases leaf expansion and thus photon capture. We examined the growth response and photosynthetic capacity of vegetable and ornamental greenhouse crops under a red-fluorescent plastic, plastics with varying transmission percentages of blue light (from 6% to 20%), and an uncovered greenhouse control with a 40% greater PPFD. When the transmitted PPFD was similar, decreasing the percentage of blue light increased the extension growth for some but not all species tested. Transmitted PPFD had a more pronounced effect on extension growth than the percentage of blue light. Lettuce shoot dry mass was greater under the red-fluorescent film than the other covered treatments and similar to the uncovered control with 40% more light. Regardless of the transmission spectrum, decreasing the transmitted PPFD reduced tomato fruit fresh mass and generally decreased the number of flowers ornamental on the species. Maximum photosynthetic rate (A_max), stomatal conductance (g_sw), and quantum yield of photosystem II (PhiPSII) consistently decreased as the percentage of blue light transmission decreased, but this did not correlate to biomass accumulation. An experimental red-fluorescent film had cultivar and species-specific effects on growth, highlighting both its potential for leafy greens and potential challenges for greenhouse crops with a greater quantum requirement. Full article

This study was performed to investigate the effects of dietary yeast culture (YC) supplementation on growth performance, digestive function, intestinal inflammatory response, and microbiota composition of largemouth bass Micropterus salmoides (LMB). Six diets were formulated with graded levels of YC (0, 5, 10, 15, 20, and 30 g/kg), referred to as CON, YC5, YC10, YC15, YC20, and YC30, respectively. Each diet was assigned to four replicate tanks of LMB juveniles (initial body weight 8.11 ± 0.05 g) with twenty fish per tank. After an 8-week feeding trial, final body weight and specific growth rate showed an increasing trend with 5~20 g/kg YC and reached a maximum at 15 g/kg YC. Feeding ratio decreased, but feed efficiency ratio (FER) improved in response to dietary YC inclusion, and FER was higher in the YC10 fish than in the YC5, YC20, and YC30 fish. Proximate composition (moisture, protein, and lipid) of the whole fish was not affected by dietary YC levels. The activities of intestinal lipase and trypsin were higher in the YC10 fish, while the relative expression of interleukin-8 (il-8) and il-1β was downregulated in the hindgut of the YC15 fish compared with the CON fish. Histological examination showed that the villus height of the midgut, together with goblet cell density of the foregut and midgut, was higher in the YC10 and YC30 fish than in the CON fish. 16S rRNA sequencing showed that Proteobacteria, Fusobacteria, and Firmicutes dominated the intestinal microbiota in LMB. The decrease in harmful Mycoplasma accounted for the dramatic change in Firmicutes abundance, while the increase in Cetobacterium (specifically C. somerae) accounted for the change in Fusobacteria abundance in the gut of the YC10 and YC30 fish compared with the CON fish. The increase in the beneficial Endozoicomonas was the main reason for the change in Proteobacteria abundance in the intestine of the YC30 fish as compared with the CON fish. Taken together, the alteration of intestinal microbiota composition contributed to the improved digestive function and feed utilization in LMB fed YC-supplemented diets. Based on growth performance, the optimal YC level in the diet for LMB was 15 g/kg. Full article

Phase change materials (PCMs) have significant potential for utilization due to their high energy storage density and excellent safety in energy storage. In this research, a flexible heat storage device using the stable supercooling of sodium acetate trihydrate composite is developed, enabling on-demand heat release through controlled solidification initiation. The solidification and heat release characteristics are investigated in experiments. The results indicate that the heat release characteristics of this heat storage device are closely linked to the crystallization process of the PCM. During the experiment, based on whether external intervention was needed for the solidification process, the PCM manifested two separate solidification modes—specifically, spontaneous self-solidification and triggered-solidification. Meanwhile, the heat release rates, temperature changes, and crystal morphologies were observed in the two solidification modes. Compared with spontaneous self-solidification, triggered-solidification achieved a higher peak surface temperature (53.6 °C vs. 46.2 °C) and reached 45 °C significantly faster (5 min vs. 15 min). Spontaneous self-solidification exhibited slower, uncontrollable heat release with dendritic crystals, while triggered-solidification provided rapid, controllable heat release with dense filamentous crystals. This controllable switching between modes offers key practical advantages, allowing the device to provide either rapid, high-power heat discharge or slower, sustained release as required by the application. According to the crystal solidification theory, the different supercooling degrees are the main reasons for the two solidification modes exhibiting different solidification characteristics. During solidification, the growth rate of SAT crystals exhibits substantial disparities across diverse experiments. In this research, the maximum axial growth rate is 2564 μm/s, and the maximum radial growth rate is 167 μm/s. Full article

Despite the growing application of storage for curtailment mitigation, its cost-effectiveness remains uncertain. This study evaluates the Levelized Cost of Storage, which also represents an implicit threshold revenue, for Lithium-ion Battery Energy Storage Systems deployed for photovoltaic curtailment mitigation. Specifically, the LCOS is assessed—using a mathematical simulation model—for various curtailment scenarios defined by maximum levels (10–40%), hourly profiles (upper limit and proportional), and growth rates (2, 5, and 10 years) at three storage system capacities (0.33, 0.50, 0.67 h) and two European locations (Cagliari and Berlin). The results indicate that the LCOS of batteries deployed for curtailment mitigation is, on average, comparable to that of systems used for bulk energy storage applications (155–320 EUR/MWh) in Cagliari (180–410 EUR/MWh). In contrast, in Berlin, the lower and more variable photovoltaic generation results in significantly higher LCOS values (200–750 EUR/MWh). For both locations, the lowest LCOS values (180 EUR/MWh for Cagliari and 200 EUR/MWh for Berlin), obtained for very high curtailment levels (40%), are significantly above average electricity prices (108 EUR/MWh for Cagliari and 78 EUR/MWh for Berlin), suggesting that BESSs for curtailment mitigation are competitive in the day-ahead market only if their electricity is sold at a significantly higher price. This is particularly true for lower curtailment levels. Indeed, for a curtailment level of 10% reached in 5 years, the LCOS for a 0.5 h BESS capacity is approximately 255 EUR/MWh in Cagliari and 460 EUR/MWh in Berlin. The study further highlights that the curtailment scenario significantly affects the Levelized Cost of Storage, with the upper limit hourly profile being more conservative. Full article

Salinity serves as a critical environmental factor influencing the physiological and morphological characteristics of Spirulina, a filamentous cyanobacterium used for food production and commercial purposes. This study examined a Spirulina strain’s responses to different salinity levels (10–45 ppt) through three independent laboratory experiments that determined growth, productivity, and size structure. Growth across salinity treatments was assessed by monitoring optical density in 24-well microplates over 20 days and estimating specific growth rates using a logistic growth model. Primary productivity under different salinity and light conditions was measured using light and dark bottle experiments to calculate gross primary productivity (GPP) and to estimate photosynthetic efficiency through linear regression of GPP against light intensity. The size structure was assessed through tube-based experiments and image analysis, with organism sizes categorized and analyzed to identify salinity-induced patterns in filament structure. The study demonstrated that the Spirulina strain achieved its greatest growth at 10 ppt yet produced the highest photosynthetic efficiency between 27 and 45 ppt because it reallocated energy during salinity stress. The morphological analysis revealed that the Spirulina strain produced medium-sized filaments between 400 and 799 µm at elevated salinity levels, and our analysis confirmed substantial variations in size structure. The Spirulina strain demonstrates both physiological and morphological plasticity when exposed to salinity changes. The cultivation of the Spirulina strain at 27 ppt provides conditions that support moderate growth, enhanced productivity, and manageable morphological shifts while using its natural salinity tolerance to improve the efficiency and scalability of production for diverse biotechnological applications. Full article

The investment–saving relationship has been the subject of much debate. On the one hand, there is the conventional mainstream neoclassical school of thought that advocates for the idea that saving determines investment. On the other hand, heterodox economists (mainly in the post-Keynesian/structuralist tradition) posit an inverse relationship between these variables. This article empirically investigates the direction of causality in order to contribute to the existing literature on the topic. To this end, two Granger panel tests are applied to a dataset of 106 countries over the period from 1980 to 2023. The econometric techniques used are effective in accounting for both cross-sectional dependence and heterogeneity in the data. In summary, our findings align with the theoretical models that posit bidirectional causality as the most probable explanation of the mechanism driving investment and saving. More specifically, they are consistent with post-Keynesian (demand-led) assumptions describing an open economy operating below its maximum potential growth rate within a current account solvency constraint. Full article

We propose an adaptive multi-timescale particle filter (AMTS-PF) for nonlinear state estimation in wastewater treatment plants (WWTPs) to address multi-scale temporal dynamics. The AMTS-PF decouples the problem into minute-level state updates and hour-level parameter refinements, integrating adaptive noise tuning, multi-scale entropy-driven feature extraction, and dual-timescale particle weighting. It dynamically adjusts noise covariances via Bayesian fusion and uses wavelet-based entropy analysis for adaptive resampling. The method interfaces seamlessly with existing WWTP control systems, providing real-time state estimates and refined parameters. Implemented on a heterogeneous computing architecture, it combines edge-level parallelism and cloud-based inference. Experimental validation shows superior performance over extended Kalman filters and single-timescale particle filters in handling nonlinearities and time-varying dynamics. The proposed AMTS-PF significantly enhances the accuracy of state estimation in WWTPs compared to traditional methods. Specifically, during the 14-day evaluation period using the Benchmark Simulation Model No. 1 (BSM1), the AMTS-PF achieved a root mean square error (RMSE) of 54.3 mg/L for heterotroph biomass (XH) estimation, which is a 37% reduction compared to the standard particle filter (PF) with an RMSE of 68.9 mg/L. For readily biodegradable substrate (Ss) and particulate products (Xp), the AMTS-PF also demonstrated superior performance with RMSE values of 7.2 mg/L and 9.8 mg/L, respectively, representing improvements of 24% and 21% over the PF. In terms of slow parameters, the AMTS-PF showed a 37% reduction in RMSE for the maximum heterotrophic growth rate (μH) estimation compared to the PF. These results highlight the effectiveness of the AMTS-PF in handling the multi-scale temporal dynamics and nonlinearities inherent in WWTPs. This work advances the state-of-the-art in WWTP monitoring by unifying multi-scale temporal modeling with adaptive Bayesian estimation, offering a practical solution for improving operational efficiency and process reliability. Full article

Microcystis aeruginosa is a cyanobacterium frequently associated with toxic blooms in eutrophic freshwater systems. Certain strains produce microcystins (MCs), a group of hepatotoxins with significant ecological and public health implications. In this study, we examined the quantitative response of a temperate native M. aeruginosa strain to combinations of temperature (26, 30, and 36 °C), light intensity (30, 50, and 70 µmol photons·m⁻²·s⁻¹), and N:P ratio (10, 100, 150), using a full-factorial experimental design. Growth parameters (µ, lag phase duration, and maximum cell density), chlorophyll-a production, and MC-LR synthesis were modeled using Gompertz, linear, and dynamic approaches. High temperature and irradiance increased the specific growth rate but decreased final biomass, while elevated N:P ratios shortened the lag phase. MC-LR production peaked under low temperature, low irradiance, and low N:P ratio. Although MC-LR synthesis did not correlate positively with growth rate, and the environmental conditions maximizing growth differed from those enhancing toxin production, a population-level coupling between both processes was observed using the Long model. These findings suggest that MC-LR synthesis in M. aeruginosa is not merely a metabolic by-product of growth, but a context-dependent trait with potential adaptive significance. Full article

This study investigated the potential of Yarrowia lipolytica, an oleaginous yeast, for producing lipid-rich biomass and its application in food technology. According to EFSA guidelines, lipid-rich biomass is recognized as a novel food with potential nutritional and technological value. However, cost-effective and scalable production of such biomass remains a challenge. The yeast was cultured in a nitrogen-limited medium using a cost-containment strategy based on the use of waste carbon sources, such as post-frying oil and untreated tap water. The composed batch culture approach studied in the experiments presented an example that reduces the cost of yeast biomass biosynthesis. This research aimed to characterize the biomass to assess its nutritional quality and suitability for food applications. Cultures were conducted in a laboratory bioreactor with a working volume of 4 litres. Key kinetic parameters were determined, including biomass yield (X), maximum lipid concentration (Lmax), lipid yield, protein yield relative to substrate and the specific rate of lipid synthesis or protein content and other cellular components. The biomass of Y. lipolytica demonstrated a high lipid content (39.43–50.53%), with significant levels of protein (24.16–27.03%) and unsaturated fatty acids, including oleic acid (62.73–66.44%) and linoleic acid (19.40–21.40%). Lipid-rich biomass produced in cultures with shorter times (20 h), which ended in the logarithmic growth phase, exhibited lower oxidative stability than longer cultures (65 h), which ended in the stationary growth phase. The results of this study highlighted that waste carbon sources and untreated tap water did not significantly impact the biomass yield or the nutritional profile, but did affect the stability of the produced oil. The biomass of Y. lipolytica, containing over 20% lipids, could serve as a promising raw material for food technology, providing a sustainable alternative to traditional vegetable oils. This work makes an important contribution to the development of alternative lipid sources by integrating waste processing in bioreactor-scale culture and kinetic modelling. Full article

This study systematically investigated two ecotypes of Ulva prolifera, the dominant species responsible for green tides in the Yellow Sea, classified as Subtype I (strain I08-1) and Subtype II (strain QD-7). Both subtypes produce positively phototactic biflagellate gametes with oval/pear-shaped morphology but exhibit distinct cellular dimensions. Subtype I gametes demonstrated significantly larger cell sizes, with long and short axes measuring 6.55 μm and 4.62 μm, respectively, compared to Subtype II’s dimensions of 6.46 μm (long axis) and 3.03 μm (short axis). Developmental analysis revealed striking morphological divergence at the 6-day germling stage: Subtype I attained an average length of 1301.14 μm, more than doubling Subtype II’s 562.25 μm. Superior growth kinetics were observed in Subtype I, exhibiting enhanced specific growth rates (SGRs) across multiple parameters—main stem length (8.58% vs. 3.55%), primary branch elongation (19.17% vs. 12.59%), main stem width expansion (17.29% vs. 5.00%), and biomass accumulation (41.90% vs. 40.96% fresh weight). Chlorophyll quantification confirmed significantly higher pigment content in Subtype I. Pre-co-culture photosynthetic profiling demonstrated Subtype I’s superior quantum efficiency (α = 0.077 vs. 0.045) with marked differences in regulated energy dissipation (YNPQ) and non-photochemical quenching (NPQ). Post-co-culture physiological adaptation was evident in Subtype II, showing significant elevation of non-regulated energy dissipation quantum yield (YNO) and eventual surpassing of maximum electron transport rate (ETRmax) compared to Subtype I. These findings establish that U. prolifera employs robust photoprotective and thermal adaptation strategies under natural photothermal conditions. Crucially, YNO-based analysis revealed Subtype II’s enhanced high-light protection mechanisms and superior adaptability to intense irradiance environments. This research elucidates ecotype-specific environmental adaptation mechanisms in U. prolifera, providing critical insights for optimizing green tide mitigation strategies and advancing ecological understanding of algal bloom dynamics. Full article

Introduction: Hypoglossal nerve stimulation (HNS) “Inspire_© therapy” has garnered popularity among obstructive sleep apnea (OSA) patients seeking an alternative to continuous positive airway pressure (CPAP) therapy. The growth in HNS has been particularly high in older adults living with OSA. Consistent and proper use of HNS in the geriatric population faces unique age-associated barriers: a high rate of multiple chronic conditions (MCC) and polypharmacy (being on five or more drugs). Early recognition and patient-centered management of these barriers will allow older patients to obtain maximum benefits from HNS. HNS has distinct advantages in the geriatric population because it overcomes many concerns related to CPAP therapy adherence, such as mechanical limitations due to manual dexterity, maxillofacial anatomy, dental issues such as usage of dentures, allergy/otolaryngology-related disorders, and pre-existing post-traumatic stress disorder-related claustrophobia. This paper describes how we worked with older patients with OSA and their care partners to overcome these barriers so patients can continue to derive cardiovascular, neurologic, and quality of life benefits resulting from optimal OSA management. These benefits are especially important in the older population because of higher rates of comorbidities (dementia, coronary artery disease, and atrial fibrillation) exacerbated by sub-optimally treated OSA. In this article, we describe our clinical experience with elderly patients on Inspire_© therapy, with a focus on the everyday difficulties faced by these patients and the measures implemented to address and mitigate these barriers. Methods: A retrospective chart review was conducted to identify patients aged 65 and above who underwent hypoglossal nerve stimulator insertion. Experiences of older patients during and after the insertion procedure were documented and compared to a younger population of patients on HNS therapy. We specifically collected information on difficulties encountered during activation or follow-up visits and compared them between the different age groups. Using this information, we identified areas to improve treatment adherence from the patients’ perspectives. Results: We identified 43 geriatric (65 to 86 years old) patients who received the Inspire implant at a tertiary academic medical center and compared them to a younger population of 23 patients. Most common challenges noted—with a potential to impact adherence—included orofacial and lingual neuropraxia (ischemic or demyelination-induced neuropathy) at activation, cognitive dysfunction (memory problems), preexisting anxiety, and insomnia. Other difficulties that are less commonly reported but equally important to consistent and proper use of HNS included headaches, concerns of device malfunction, change in comfort levels after cardiac procedures, and general intolerance of the device. The older patient population had a statistically significant higher incidence of cognitive difficulties (30.2% vs. 4.4%) and a smaller social support system (62.8% vs. 91.3%) affecting device usage compared to the younger population. There were no statistically significant differences in the rates of other more commonly reported adverse effects such as headaches, dry mouth, and anxiety between the two age groups. Conclusion: Despite several challenges faced by geriatric patients, Inspire_© hypoglossal nerve stimulation remains a viable, alternative treatment option for OSA with improved tolerance and adherence compared to CPAP. After identifying less commonly reported barriers such as cognitive decline, sensory deficits, and decreased social support systems, minor adjustments and appropriate education on use allows older patients to correctly use and benefit from Inspire_© device therapy, with subsequent improvement in sleep and overall quality of life. Full article

Aquaponics is an integrated method of aquatic animal and plant cultivation in a closed recycling system where the wastewater from aquatic animals is purified by microbes, which transform pollutants into nutrients for plants at the end of the chain. This technology allows to the efficiency of the area to be increased by a combination of cultivated plants and aquatic animals. Aquaponics produces environmentally friendly products by reducing fertilizer use and wastewater volume, increasing the extent of reuse by up to >90%. A promising way to increase efficiency in aquaponics is to use bacterial preparations (probiotics). This will allow control of the development of pathogens in the growing system, improving water quality and the growth rate of aquatic organisms. This paper overviews the experience of using probiotic preparations in aquaponic systems. It is shown that probiotics are able to increase the survival rate of aquatic organisms, improve the hydrochemical regime in recirculating aquaculture systems, and mitigate the risk of pathogenic contamination. There are a number of problems in aquaponics that prevent it from becoming more widespread and achieving maximum productivity, including problems with optimal pH and temperature, problems with nutrient and oxygen depletion, as well as diseases caused by phytopathogens and fish pathogens. The probiotics used do not take into account the biological needs of all components of the aquaponic system. The development of probiotic preparations from soil bacteria of the genus Bacillus will allow us to create a new class of probiotics specifically for aquaponics. Such preparations will work in a wide pH range, which will allow us to achieve maximum productivity for all components of aquaponics: animals, plants and bacteria. Full article

Docosahexaenoic acid (DHA), a long-chain polyunsaturated fatty acid, plays a critical role in animal growth, inflammatory regulation, lipid metabolism, and neurological functions. However, the optimal dietary requirement of DHA for tiger puffer remains unknown. This study systematically investigated the effects of different dietary DHA levels on the growth performance, body composition, hematological parameters and tissue physiology of tiger puffer (average initial body weight 17.78 ± 1.92 g). Six experimental diets with graded DHA concentrations (0.09%, 0.57%, 1.35%, 1.61%, 2.28%, and 3.08% dry matter) were formulated. The feeding experiment was carried out in a seawater flow-through system for eight weeks, with each diet assigned to three replicate tanks. Based on the regression analysis of weight gain and specific growth rate, the maximum values were observed at the dietary DHA level of 1.75% and 1.88%, respectively. Appropriate DHA levels also significantly improved the muscle protein synthesis and lipid metabolism, and strengthened the intestinal morphology. Furthermore, a threshold for efficient DHA deposition in muscle was identified, beyond which excess DHA (3.08%) may be β-oxidized and therefore largely wasted. In conclusion, the optimal dietary DHA level for juvenile tiger puffer should be within the range of 1.75–1.88%. Full article