Search Results (233)

We investigate $\lambda$-constacyclic codes of length n over finite commutative local rings R of characteristic p and order $q^5,$ where $q=p^m$ is an odd prime power, whose Jacobson radical $\mathcal{N}$ satisfies ${\mathcal{N}}^3=0\ne {\mathcal{N}}^2$, under the coprimality condition $\gcd (n,p)=1$. In this setting, exactly two radical types occur, namely $(3,1)$ and $(2,2)$, determined by the dimensions of $\mathcal{N}/{\mathcal{N}}^2$ and ${\mathcal{N}}^2$. For each type, we provide an explicit classification of the underlying rings and analyze the induced radical filtration of the ambient algebra $A_{\lambda }=R\left[X\right]/⟨X^n-\lambda ⟩$. We prove that every $\lambda$-constacyclic code is uniquely determined by its residual component in $A_{\lambda }/\mathrm{J}\left(A_{\lambda }\right)$ together with two torsion components arising from the radical chain $\mathrm{J}\left(A_{\lambda }\right)\supset \mathrm{J}{\left(A_{\lambda }\right)}^2\supset 0$. This residual–torsion decomposition yields explicit generating sets; in particular, every $\lambda$-constacyclic code admits a generating set consisting of at most five elements. Furthermore, we derive exact enumeration formulas for all $\lambda$-constacyclic codes. In the type $(2,2)$ case, the enumeration is governed by linear-algebraic constraints over the Chinese Remainder Theorem residue fields and, in the anisotropic class, depends on quadratic character values determined by the extension degrees. In the type $(3,1)$ case, the enumeration is controlled by the dimension of the radical of the induced symmetric bilinear form on the top radical layer, equivalently by the rank class of the associated canonical matrix. Full article

Understanding salmonid spawning dynamics is critical for conserving cold-water river ecosystems amid increasing human and climate pressures. This study developed and validated a species-specific eDNA (Salmo cf. trutta and Thymallus thymallus) and evaluated its performance for seasonal spawning activity monitoring using droplet digital PCR (ddPCR). Species-specific primers and probes targeting mitochondrial nd5 (S. trutta) and cytb (T. thymallus) genes were designed and optimized as a duplex assay. Performance assessments included in vitro validation, cross-amplification testing, and determining the LOB, LOD, and LOQ. Field validation over a year at two spawning sites in the Gradac River, Serbia, involved seasonal eDNA sampling, filtration, extraction, and ddPCR analysis. Fish community composition was also assessed with electrofishing and metabarcoding. The assay showed high specificity and sensitivity, with LODs of 0.14 cp/µL and LOQs of 0.99 and 1.25 cpµL for S. trutta and T. thymallus. S. trutta eDNA peaked in late autumn during spawning, while T. thymallus remained at or below detection limits, reflecting its lower abundance and different spawning season. Filter type affected filtration efficiency but not eDNA yield. These findings confirm ddPCR-based eDNA as a powerful, non-invasive tool for monitoring salmonid spawning and seasonal changes, supporting adaptive fisheries management and conservation amid environmental changes. Full article

Background: The updated Schwartz and CKiDU25 bedside (SCr-based) formulae for the estimated glomerular filtration rate (eGFR) in children are defined by a constant term (with the latter formula dependent upon age and sex) multiplied by the ratio of patient’s height (m) to SCr (mg/dL). However, the Schwartz formula can severely underestimate the measured GFR (mGFR) at higher mGFR levels. Methods: For a single-center cohort of 92 pediatric kidney transplant recipients, we statistically determined if the log{eGFR} at 1 mo and 6 mo post-transplant might further depend upon patient demographics or height, indicating the inadequacy of these formulae for properly predicting the mGFR. We also determined how the log{SCr} at 1 mo and 6 mo post-transplant might depend upon patient demographics and height, helping to corroborate any arrived-at improved functional form for the eGFR. Results: Overall, our cohort received good-quality donor kidneys; however, both eGFR formulae calculated that the percentage of recipients with an eGFR < 60 mL/min/1.73 m² at 1 mo and 6 mo post-transplant was 26–28%. Furthermore, neither the updated Schwartz nor the CKiDU25 bedside formulae adequately controlled for the influence of patient height on SCr; in fact, the patient height squared was superior to its unidimensional value at accounting for the sharp increase in SCr that normally occurs as children grow from infancy to young adulthood (p < 0.000001 at mo1, p = 0.000003 at mo6 for the updated Schwartz bedside formula; p = 0.0009 at mo1, p = 0.005 at mo6 for the CKiDU25 bedside formula). The log{SCr} was also best fitted by a linear regression model that controlled for the log{patient height squared} (p < 0.000001 at both mo1 and mo6). Conclusions: A statistically more accurate eGFR formula should be based on using a power function (power > 1) for patient height rather than its unidimensional value. Full article

Implantable artificial kidneys represent a promising alternative for patients with end-stage renal disease (ESRD), aiming to overcome the limitations of conventional dialysis through the integration of microfluidic and electrokinetic technologies. In this study, we present a sawtooth electrode microfluidic chamber that achieves blood cell separation via negative dielectrophoresis at a record-low operating voltage of 1.4 V, representing a fivefold reduction compared with rectangular electrode designs and supporting potential integration into implantable artificial kidney systems. A microfluidic chip incorporating an asymmetric sawtooth electrode geometry was developed to enhance local electric field gradients while reducing power consumption. Device performance was investigated using COMSOL Multiphysics simulations. Response Surface Methodology (RSM) based on a Box–Behnken design was employed to optimize the number of teeth per unit length (N), sawtooth height (H), and applied voltage (V), while excitation frequency was fixed at 1 MHz and flow velocity was maintained constant at 0.1 µL·min⁻¹. Statistical analysis was conducted using analysis of variance (ANOVA) in Minitab (Version 27; Minitab, LLC, State College, PA, USA, 2024). The optimization model showed strong predictive capability (R² = 95.8%) and identified applied voltage (59.45% contribution) and sawtooth height (33%) as the dominant factors affecting separation efficiency, with a significant H × V interaction (p = 0.023). Comprehensive voltage-response mapping over the range of 0.8–4.0 V revealed four operational regimes, including a previously unreported high-voltage failure zone above 2.8 V, where electrothermal flow and electroporation degrade performance. Under physiological conductivity conditions, the optimized design maintained a separation efficiency of 78.3% at 1.4 V with a tip temperature rise of only 1.2 °C, while full recovery of performance was achieved at 2.2 V. Cell-specific separation efficiencies reached 97.3% for white blood cells, 95.8% for red blood cells, and 84.7% for platelets, reducing the downstream cellular load by 92.6%. These findings demonstrate that the proposed low-voltage, high-efficiency separation platform has strong potential as a cellular pre-filtration module in implantable artificial kidney systems and other lab-on-chip biomedical devices. Full article

This study assesses the technical, operational, environmental, and economic feasibility of integrating alkaline water electrolysis (AEL) using on-site measured surplus electricity from two 20 MW natural-gas turbogenerators installed at a Central Processing Facility (CPF) in a Colombian oilfield. Unlike approaches based on modeled profiles, the analysis relies on more than 31,000 experimental records of gas consumption and active power, enabling an accurate characterization of the structural availability of energy surpluses under real operating conditions. A specialized industrial water treatment and purification company was consulted and provided with the physicochemical characterization results obtained from process water samples analyzed by an accredited laboratory. Based on these parameters, the technical supplier confirmed the feasibility of designing a multistage treatment train, including equalization, filtration, clarification, activated carbon, ultrafiltration, and reverse osmosis, capable of achieving final conductivities at or below 5 µS/cm. This water quality level is compatible with typical industrial alkaline electrolysis requirements and in line with technical specifications commonly aligned with ASTM and ISO standards for pressurized AEL systems. A strategic comparison between PEM and AEL technologies, supported by IFE/EFE matrices and sensitivity analyses, identified alkaline electrolysis as the optimal alternative under a stable electrical profile and capital expenditure constraints. Energy sizing for scenarios between 1.5 and 10 MW, assuming continuous 24 h operation and an average specific consumption of 50 kWh/kg H₂, yields productions between 0.5 and 3.5 t H₂/day, with electrical efficiencies above 70%. A 20-year financial analysis indicates a techno-economic threshold near 3 MW (NPV > 0; IRR > WACC), with optimal performance in the 6.5–10 MW range and payback periods between 2 and 4 years under internal valorization of the surplus electricity. From an environmental perspective, the produced hydrogen is classified as low-carbon rather than “green” due to its thermal origin; however, the integration improves the turbines’ operating regime and valorizes surplus electrical exergy that was previously unused, providing a replicable strategy for industrial assets with self-generation and treatable water availability. Full article

The valorization of poultry bone by-products into high-value bioactive ingredients aligns with the principles of a sustainable circular bioeconomy. This study established an integrated process for the production, identification, and validation of bioactive antioxidant peptides from Xuefeng black-bone chicken bones (BCB). Alcalase was selected as the optimal protease due to its superior performance in both the degree of hydrolysis and antioxidant activity under the optimized conditions. Using response surface methodology (RSM), the optimal hydrolysis conditions were determined as 50 °C, pH 10.18, and 4.2 h, resulting in a hydrolysate with a hydrolysis degree of 25.10% and ABTS radical scavenging activity of 84.36%. Upon ultrafiltration, the <3 kDa fraction demonstrated a significantly higher antioxidant capacity than the crude hydrolysate. Further purification through gel filtration chromatography yielded the F3 sub-fraction (predominantly <1 kDa peptides), which exhibited the most potent activity across all four antioxidant assays conducted (ABTS, DPPH, hydroxyl radical scavenging, and reducing power). A liquid chromatography–tandem mass spectrometry (LC-MS/MS) analysis of F3 led to the identification of 21 peptide sequences. An in silico screening based on bioactivity and toxicity predictions pinpointed three promising candidates: DYPF, WDY, and FGYK. These peptides were chemically synthesized and validated to possess significant in vitro radical scavenging activities against both DPPH and hydroxyl radicals. Molecular docking simulations revealed that all three peptides could spontaneously bind to the Keap1 protein with a high affinity (binding energy < −7.0 kcal/mol), primarily through hydrogen bonds and hydrophobic interactions, suggesting a possible molecular mechanism that may involve the Keap1-Nrf2-ARE antioxidant pathway. This computational insight provides a testable hypothesis for their bioactivity, the verification of which is contingent upon future studies demonstrating their cellular delivery and intracellular action. This work not only provides a sustainable strategy for BCB utilization but also identifies potent antioxidant peptides with potential applications in functional foods and nutraceuticals. Full article

Currently, the installation of distributed energy sources is growing rapidly, especially renewable sources, for which the goal is to increase energy self-sufficiency across certain parts of the distribution network. The optimization of electricity production and distribution is key to achieving this goal. To optimize the energy distribution system, filters are increasingly being installed to compensate for reactive power, mitigate voltage unbalance, and reduce higher harmonics in small parts of the electrical system and even for single loads. This article verifies the filtration efficiency of a group of single-tuned passive harmonic filters. Two groups are investigated: a group of real filters and a designed optimal filter. This investigation was performed in three important parts: Firstly, measurements of the power quality parameters were taken in a real system (laboratory measurements). Secondly, the configuration of the optimal filter group was calculated, assuming the same reactive power and tuning frequencies as in a real system. In the group structure of such filters, the biggest problem is properly sharing the total reactive power between the filter branches. Thirdly, both filter structures (real and optimal) are compared based on harmonic reduction indexes and the filter efficiency index. Full article

Bio-inspired and bio-based materials are increasingly recognized as powerful enablers of climate-responsive and low-carbon architecture. By learning from natural systems, such as adaptability, self-regulation, and resource efficiency, these materials offer promising solutions to the escalating environmental pressures faced by the built environment. However, their systematic integration into building design remains limited, particularly in tropical monsoon climates. To address this gap, this study applies the Decision-Making Trial and Evaluation Laboratory (DEMATEL) method to identify, prioritize, and map the interdependencies among ten bio-based and bio-inspired strategies for sustainable building design. The results highlight five dominant solutions: living building systems, bio-composite exterior cladding for weather resistance, mycelium-based insulation for humidity control, bio-based natural ventilation and passive cooling, and bio-inspired self-shading systems. The causal analysis reveals three key characteristics: (1) living building systems function as a central integrative nexus, (2) bio-composite cladding acts as a primary driver of durability and climate resilience, and (3) bio-based water filtration and local timber exhibit lower systemic leverage despite their environmental benefits. Theoretically, this study advances biomimetic design research by introducing a causal, system-level framework for understanding interactions among nature-inspired strategies. Practically, it provides architects, engineers, and policymakers with an evidence-based decision-support tool to prioritize climate-adapted, bio-inspired solutions, contributing to the development of resilient and regenerative architecture in rapidly changing climates. Full article

During the discharge process of a salt cavern compressed air energy storage (CAES) system, high-speed air flow may entrain salt slag from the cavern floor, posing a threat to pipeline safety. Currently, there is a lack of in-depth research into the transient mechanisms of the entrainment process, particularly the influence of particle shape. This study employs a CFD-DEM coupling approach to conduct, for the first time, a high-fidelity simulation of slag entrainment dynamics during the initial discharge phase of a salt cavern CAES system, with a focus on the motion patterns of three particle shapes: spherical, conical, and square. Results show that: (1) during the initial discharge stage, the flow field rapidly forms vortex structures that migrate toward the wellhead, which is the core mechanism driving particle mobilization; (2) particle shape significantly affects entrainment efficiency through frictional characteristics—spherical particles are most easily entrained (maximum entrainment rate of 0.42 kg/h), while non-spherical particles tend to accumulate below the wellhead; and (3) the entrainment process exhibits strong transient characteristics: the entrainment rate peaks rapidly (approximately 0.82 kg/h) within a short time and then declines sharply, and it is sensitive to particle size, with the most entrainable particle size being around 5 mm. This study reveals the coupling mechanism between transient vortices and multi-shape particle entrainment during discharge, providing a theoretical basis for the design of filtration systems, operational risk prevention, and slag removal strategies in salt cavern CAES power plants. Full article

Objective: Glaucoma is a complex optic neuropathy characterized by the progressive loss of retinal ganglion cells (RGCs). Animal models are crucial tools for deciphering its multidimensional pathogenesis and evaluating novel therapeutic strategies. This review aims to systematically summarize the establishment methods, application advances, and future development trends of various glanimal models. Methods: The literature for this review was identified through systematic searches of electronic databases, including PubMed, Web of Science Core Collection, and Google Scholar. The search strategy utilized a combination of keywords and their variants: “glaucoma”, “animal models”, “retinal ganglion cells”, “intraocular pressure”, “neuroprotection”, “immune inflammation”, “fibrosis”, and “filtration surgery”. The search focused on articles published between 2015 and 2025 to cover the major advances of the last decade. The scope encompassed original research articles, reviews, and meta-analyses. Results: Diverse glanimal models successfully replicate different facets of glaucoma, elucidating multidimensional pathogenesis involving mechanical stress, immune inflammation, excitotoxicity, oxidative stress, and fibrosis. These models have played an indispensable role in screening neuroprotective agents, evaluating anti-fibrotic strategies, and validating the application of advanced imaging and functional assessment technologies. Current research is evolving towards model standardization, multi-factor simulation, and the integration of novel drug delivery systems and immunomodulatory strategies. Conclusions: The diversification of glanimal models provides a powerful platform for in-depth investigation of disease mechanisms and the development of innovative therapies. Future research should focus on establishing standardized models that better mimic the clinical pathological state and deeply integrating multimodal assessment technologies with targeted therapies. This will facilitate the translation of basic research into clinical applications, ultimately achieving personalized precision medicine for glaucoma. Full article

This research paper proposes a solution to reduce CO₂ emissions from a spark ignition engine’s exhaust gases by installing a filtration system on the vehicle’s exhaust pipe. The analyzed filtration system was not patented and was in the testing stage. Tests will also be carried out on the stand. The tested system can be used to reduce CO₂ levels in automotive exhaust gases and for static applications (generators, internal combustion engine test stands, fossil fuel power generation systems). The need for a system to reduce pollutant emissions emerged with the average age in Europe. In proper conditions, some vehicles can use this type of filtration system. The tested vehicle is a vehicle (produced in 2009) equipped with a 75HP Spark Ignition Engine. The CO₂ filtration system consists of a container containing a reactive aqueous solution comprising water, CaO, and MgO. Four tests were performed: the first without a filter, and the other three with the filter placed at different distances from the exhaust pipe end to the reactive solution surface. The tests consisted of evaluating the exhaust gases from the cold start of the engine and running (idle engine speed) until the engine reached the optimal operating temperature. The test procedure involved saving the data collected by the analyzer every 10 s for each of the four tests performed (the duration of a test was 1050 s). The first test (No. 1) was performed without the use of the filtering system. Tests 2, 3, and 4 were carried out using the filtering system and changing the distance between the exhaust gases’ outlet point and the surface of the aqueous substance. All tests were carried out under similar conditions. Data specific to the test of engines were collected—emissions (CO₂, CO, NO_x), ambient temperature, and exhaust temperature. The tests were analyzed and compared, and the highest CO₂ reductions without increases in CO or NO_x were observed in Tests 3 and 4. Based on the detailed analysis of the values obtained from the four tests, the system was efficient. The tests will continue on experimental engines from test stands, to develop a prototype filter for primarily static applications with internal combustion engines: test stands for engines and generators, and, after homologation, directly on vehicles. The paper aims to partially solve an important problem—reducing the level of CO₂ from the exhaust gases. The presented solution may have applicability in the automotive industry but is also feasible for static applications. Another objective is to reduce emissions from older vehicles, which are widespread in certain regions of Europe and worldwide. Full article

A huge amount of waste is produced annually by the food processing industry which must be valorized into high-value products. Therefore, the aim of this work involves the use of such wastes for production of β-glucans from medicinal basidiomycete strains which are powerful biological response modifiers in several clinical disorders. The production of β-glucans from basidiomycete strains in submerged fermentation was monitored by using monoclonal antibodies of the IgG and IgM classes as well as by Congo red assay in the presence of several agro-industrial waste products such as milk permeate, waste coffee grounds, orange peels and rice husks. Subsequently, these β-glucans were purified by using gel filtration and ion-exchange chromatography. FTIR analysis of several β-glucans was carried out to investigate their structural properties. The adsorption of β-glucans on microtiter plates was dependent on the temperature as well as on the time period of immobilization for ELISA. These mAbs can be used in a competitive ELISA for detection and quantification of β-glucans from basidiomycete mushrooms. Full article

Differential abundance analysis (DAA) is a critical task in microbiome research aimed at identifying microbial signatures that reliably characterize groups. Research suggests that microbiome systems are relatively stable and resilient, yet even small changes under certain conditions can trigger dysbiosis. The high dimensionality of microbiome datasets exacerbates the challenge of detecting such changes by posing a multiple comparison problem that requires hypothesis filtration. Standard filtration using multiple comparison correction procedures is designed for scenarios with a high number of true positives and is often too conservative for microbiome data, where the proportion of true signals can be very low. Therefore, there is a substantial need for hypothesis filtration methods tailored to microbiome data. Confidence intervals (CIs) for between-group differences offer a powerful alternative to p-value filtration, as their range simultaneously conveys information about the significance, potential magnitude, and direction of the effect, as well as the certainty of the estimate itself. Microbial data can be adequately modeled using a negative binomial (NB) distribution, and its location parameter can be robustly estimated with the Hodges–Lehmann estimator (HLE). Using synthetic and experimental data, we demonstrate that hypothesis filtration based on CIs for the two-sample HLE is a robust method for comparing microbial data. Our analysis demonstrates that the HLE-CI approach provides the same level of precision as filtration using multiple-adjustment methods while achieving significantly higher recall in microbiome DAA. The results of this study suggest that HLE-CI-based filtration can be an effective step in the search for microbiome biomarkers. Full article

Fouling is a major challenge in membrane-based filtration processes, leading to higher operating and capital costs. Developing new membranes with better fouling resistance has always been a research focus in the membrane field. In particular, designing functional surfaces which mitigate fouling is an effective approach. We successfully fabricated membranes with a graphene functional layer using a single-step laser irradiation known as laser-induced graphene (LIG) on the membrane surface. The LIG ultrafiltration (UF) membranes were prepared by directly lasing poly(ether sulfone) (PES) membrane substrates. Scanning electron microscopy demonstrated the successful ablation of the PES membranes with controlled thickness. Water filtration tests confirmed that the permeance increased by 240% as the laser power increased from 2.4 to 3.2 W; the membrane lased with the highest ablation power (LIG-P8) displayed a high water permeance of ~400 L m⁻² h⁻¹ bar⁻¹ and a corresponding bovine serum albumin (BSA) rejection of 92.5%. Fouling experiments using BSA, humic acid (HA), and sodium alginate showed better permeance recovery ratios (78–90%) with LIG membranes compared to the neat PES membrane (65–68%). LIG membranes were also evaluated for antibioufouling filtration tests, which showed exceptional biofilm resistance and potent antibacterial killing effects when treated with Staphylococcus aureus. Applied external voltage and contact time were the key variables to optimize the antibiofouling properties of the LIG UF membranes. Full article

The detailed characterization of antigen-specific serum antibodies is hindered by the lack of efficient, gentle isolation methods. In this context, standard column affinity chromatography, although a powerful purification tool, presents practical challenges, including high antigen consumption and elution conditions that risk inducing antibody polyreactivity, while conventional acidic elution often compromises antibody integrity. This study introduces a novel microscale method for isolating specific immunoglobulins using anionic detergents as mild eluents. We employed antigen-functionalized hydrogel microarrays and magnetic beads as micro-immunosorbents. Among the tested detergents, sodium lauroyl glutamate (SLG) was optimal, achieving up to 78.3% recovery of functional antibodies. The optimized protocol, including recovery via G25-Sephadex gel filtration, effectively isolated specific antibodies from complex serum, retaining 58.5–85.3% of their functional bioactivity. Multiplex immunoassays confirmed the high specificity of the isolated antibodies and the lack of detergent-induced polyreactivity. The method was successfully adapted to isolate both specific antibodies (virus, dietary, and autoimmune) and total IgG, demonstrating versatility across platforms. This work establishes a robust, efficient, and gentle workflow for obtaining high-purity, bioactive antibodies, enabling their subsequent in-depth analysis for research applications. Full article