Gradual Decrease Research Articles

Effects of carbon dioxide addition on soot dynamics in ethylene/air inverse diffusion flames: An experimental and computational analysis

The effects of carbon dioxide (CO2) addition to ethylene (C2H4)/air inverse diffusion flames (IDFs) to the air stream on soot formation characteristics are investigated with the addition ratio of 0-13.64%. The planar laser-induced fluorescence (PLIF) and planar laser-induced incandescence (PLII) techniques, in conjunction with CoFlame and Chemkin code simulations were utilized to assess the distributions of Polycyclic Aromatic Hydrocarbons (PAHs) and Soot Volume Fraction (SVF). The findings indicate that increasing CO2 addition results in a gradual decrease in the mole fraction of hydroxyl (OH) radicals and flame temperature, accompanied by a reduction of approximately 15% in the reaction zone height in experimental observations and 19% in simulations. The inhibition of soot formation is evident through a consistent decline in the normalized total SVF, a decrease in the peak volume fraction of radial soot distribution, and reduced total SVFs observed across different flame sections at varying heights. In the meanwhile, increasing the CO2 doping ratio significantly reduces the peak signal intensity of PAHs, particularly affecting high molecular weight PAHs (A3-A4, A2-A3) with reductions of up to 75.5%. Furthermore, reductions are noted in the rates of soot inception and subsequent surface growth, accompanied by an upward displacement of the initial inception and growth location. The condensation of PAHs controls the soot surface growth. The thermal and chemical effects of CO2 were differentiated by employing the virtual substance FCO2. The results suggest that the thermal effect of CO2 lowers flame temperature, reduces combustion intensity, and consequently inhibits soot nucleation. The chemical effect of CO2 competes for H radicals through the reverse reaction of CO+OH <=> CO2+H. This process suppresses the formation and growth of PAHs, consequently leading to a reduction in soot production.

The generation mechanism of cutting heat and the theoretical prediction model for temperature on the rake face of the cutting tool in Zirconia ceramics

Cutting temperature and its distribution are crucial factors influencing tool strength and wear rate, due to the hardness and brittleness of Zirconia (ZrO2) ceramics, significant challenges arise in both direct temperature measurement in the cutting zone and theoretical analysis of cutting heat. Thus, focusing on the turning characteristics of ZrO2 ceramics, this study analyzes the mechanism of cutting heat generation and proposes utilizing thermodynamic state equations to determine the cutting heat source on rake face of tool. Based on the heat source method, a theoretically prediction model for temperature distribution on rake face is established. This model considers primary cutting parameters, workpiece material properties, crack fracture characteristics of the machined surface, and thermal characterizations of the tool material. The relationship between tool wear and cutting temperature is experimentally analyzed to determine the characteristic temperature that indicates the initial stage of tool wear. The validity of the theoretical model is verified, as the predicted results show high consistency with experimental results within the range of experimental parameters, with a relative error within 15.2 %.The results reveal the highest temperature during brittle cutting occurs within the cutting layer area, with the highest temperature occurring approximately 50 μm from the tool tip, followed by a gradual decrease beyond 150-200 μm. This study also demonstrates that cutting heat in ceramic turning does not solely originate from friction heat between tool flank-workpiece but also includes impact heat from tool rake face-workpiece, which under certain cutting parameters exerts a more significant influence on cutting temperature. This model can facilitate the selection and optimization of cutting process parameters for brittle materials and provide a theoretical basis for analyzing the relationship between tool thermal damage, thermophysical properties, and tool wear.

Microstructure and properties of solution-treated Mg–1.5Zn–0.4Zr–0.5Gd biological magnesium alloys at different extrusion ratios

The study investigated the influence of the extrusion ratio on the microstructure, mechanical properties, and corrosion resistance of a Mg–1.5Zn–0.4Zr–0.5Gd bio-magnesium alloy. The results showed that when the extrusion ratio was between 0 and 7.72, the proportion of dynamically recrystallized grains in the alloy gradually increased with an increase in the extrusion ratio, leading to the enhancement of its mechanical properties and corrosion resistance. Beyond an extrusion ratio of 7.72, the alloy underwent complete dynamic recrystallization, and the grain size first increased and finally tended to stabilize with an increase in the extrusion ratio. When the extrusion ratio was between 7.72 and 9.77, with an increase in the extrusion ratio, the continuous increase in the grain size led to a gradual decrease in the mechanical properties of the alloy. At the same time, the reduction in microdefects and improvement of the thermal stability in the alloy gradually enhanced its corrosion resistance. When the extrusion ratio was between 9.77 and 12.76, as the extrusion ratio increased, the dislocation area and density in the alloy gradually rised, leading to an increase in the tensile strength and yield strength, whereas the elongation and corrosion resistance gradually decreased.

The dynamic patterns of critical ecological areas in the Yellow River Basin are driven primarily by climate factors but threatened by human activities

While the identification of critical ecological areas (CEAs) has been limited by the availability of resources, funds, and land space, these areas are central for maintaining the contributions from nature and ecosystem biodiversity. Thus, in this study, CEAs were systematically identified and classified via long-term ecosystem assessment with a multifunctionality–stability–integrity framework in the Yellow River Basin (YRB). The intensity and pathways of the driving factors of CEA dynamics were also determined by the geographical detector model (GDM) and the partial least squares structural equation model (PLS-SEM). The results revealed a gradual decrease in the proportion of CEAs in the upper and lower reaches from 2005 to 2020, in contrast with a significant increase in the middle reaches. The CEAs were distributed mainly in the Sanjiangyuan and Ziwuling regions and the Qingling, Qilian, Lvliang and Taihang Mountains. The areas with low, medium, and high levels of CEAs accounted for 12.48%, 17.73% and 12.54%, respectively, of the YRB. Moreover, climate factors, especially precipitation, were the foremost drivers influencing the dynamic patterns of CEAs. However, notably, the CEAs in the YRB experienced continuous degradation from 2005 to 2020 due to intensified human activities. Our results confirmed the important role of climate factors in determining the distribution of CEAs while underscoring the necessity of mitigating human disturbances to maintain ecosystem functions. These investigations of the dynamics and drivers of CEAs based on long-term multi-dimensional ecosystem assessments could provide useful insights for developing ecological conservation and sustainable development strategies.

Вплив червоного та синього електромагнітного випромінювання на каталазну активність зародків в’юна Misgurnus fossilis L.

Photobiomodulation therapy is widely used to treat various pathological conditions. This therapy is based on the use of monochromatic light radiation. The light of the visible spectrum induces different biological effects at the molecular and cellular levels, both therapeutic and toxic. The obtained effect depends on the length of radiation, exposure, etc. One of the possible mechanisms of such influence is the regulation of pro-oxidant-antioxidant homeostasis. In order to clarify the mechanism of action of electromagnetic radiation (EMR) of different spectral composition, catalase (CAT) activity was investigated in germ cells of loach Misgurnus fossilis L. during embryogenesis. Since, loach embryos are an adequate system that reflects the physiological state of the cell both under normal conditions and as a result of the influence of various pharmacological, physical and chemical agents. The resulting zygotes were irradiated (10 min) with blue and red LEDs (λ = 460 and 660 nm, respectively). The activity of CAT was determined by the ability of hydrogen peroxi­de to form a stable colored complex with molybdenum salts. It was established that EMR of the red spectrum has the most pronounced biological effects and caused significant changes in catalase activity during embryogenesis relative to control and blue light. The maximum increase of the indicator occurs at the stage of 16 blastomeres, and at the stage of 8 and 10 divisions, a gradual decrease in enzymatic activity is observed. Irradiation by the light of the blue spectrum lasting 10 min did not cause significant changes in catalase activi­ty relative to the control at the early stages of loach embryogenesis. The obtained results suggest that CAT, one of the key enzymes of the antioxidant defense system, undergoes photoactivation under the influence of red light.

The Impact of Support and Reduction Temperature on the Catalytic Activity of Bimetallic Nickel-Zirconium Catalysts in the Hydrocracking Reaction of Algal Oil from Spirulina Platensis

The aim of this work was to investigate the hydrocracking of algae oil derived from Spirulina Platensis species catalyzed with bi-component nickel-zirconia catalysts supported onto different carriers (BEA, ZSM-5 and Al2O3) in an autoclave at 320 °C for 2 h with a hydrogen pressure of 75 bar. All catalysts were prepared using the wet co-impregnation method and were characterized by H2-TPR, XRD, NH3-TPD, BET and SEM-EDS. Before reactions, catalysts were calcined at 600 °C for 4 h in a muffle furnace, then reduced with 5%H2-95%Ar reducing mixture at 500 °C, 600 °C or 700 °C for 2 h. The obtained products were analyzed and identified by HPLC and GC-MS techniques. In addition to the investigation of the support effect, the influence of the reduction temperature of catalytic systems on the catalytic activity and selectivity of the products was also examined. The activity results show that Ni-Zr systems supported on zeolites exhibited high conversion of algal oil. A gradual decrease in conversion was observed when increasing the reduction temperature of the catalyst (from 500 °C to 600 °C and 700 °C) for BEA zeolite catalysts. The reaction products contain hydrocarbons from C7 to C33 (for zeolite-supported catalysts) and C36 (for systems on Al2O3). The identified hydrocarbons mainly belong to the gasoil fraction (C14–C22). In the research, the best catalyst for the algal oil hydrocracking reaction was found to be the 5%Ni-5%Zr/BEA system reduced at 600 °C, which exhibited the second highest algal oil conversion (94.0%). The differences in catalytic activity that occur are due to the differences in the specific surface area among the supports and to differences in the acidity of the catalyst surface depending on the reduction temperature.

Design and Demonstration of a Novel Interferometric Polarimeter for Quantitative Determination of Sugars in a Solution

Accurate quantification of sugar in food and pharmaceutical products is important to achieve the desired levels of sweetness, texture, flavor and nutritional content. This article introduces a novel polarization-sensitive interferometric method for measuring the concentration of sugar in solutions. The impact of sugar concentration is investigated by analyzing the visibility of the interference pattern using a Mach-Zehnder interferometer with an interference pattern scanning and recording system. The visibility of the interference fringes is determined by cross-sectional scanning of the fringe pattern from its center over the photodetector, followed by cut-profile analysis. As the concentration of sucrose, glucose and fructose increases, a gradual decrease in interference pattern visibility is observed, following a parabolic trend within the broader detection range of 0–14 g/50 ml. The sensor’s performance is divided into two linear regions: region-1 (0–6 g/50 ml) and region-2 (6–14 g/50 ml). In region-1, fructose exhibited the highest sensitivity of 0.0195 (g/50 ml)-1, which is 6.09 times and 1.89 times higher than glucose and sucrose, respectively. Similarly, in region-2, fructose showed a sensitivity of 0.077 (g/50 ml)-1, surpassing glucose by 3.56 times and sucrose by 2.41 times. However, sucrose achieved the lowest limit of detection of 0.0021 g/ml, which is 2.76 times and 1.71 times better than glucose and fructose, respectively. The decreasing trend in interference pattern visibility is further validated through irradiance and optical rotation measurements of the laser beam passing through the sugar solutions relative to the reference laser beam. Results from both optical techniques demonstrated good agreement, with average deviations of 1.75%, 1.72%, and 4.24% for sucrose, glucose and fructose, respectively. The proposed technique is universally applicable for measuring the concentration of transparent, optically active solutions and has the potential to be a valuable tool for quality control and optimization in the food and pharmaceutical industries.

Short-term anticorrelations between in situ averaged charge states of Fe and O in the solar wind

Observations of the Fe and O charge states in the solar wind and interplanetary coronal mass ejections (ICMEs) generally exhibit a positive correlation between the average charge states of Fe and O ($ avQ Fe $ and $ avQ O $). Because Fe and O charge states freeze at different heights in the corona, this positive correlation indicates that conditions at different heights in the corona vary as a whole. We identify short time periods in the solar wind that exhibit anticorrelations between the average Fe and O charge states and investigate their properties. We aim to distinguish whether these anticorrelations are due to the related solar sources or to transport effects (e.g., differential streaming). We study kinetic properties of the solar wind related to these anticorrelated structures as well as heavy ion differential streaming in order to infer a possible relationship between conditions in coronal source regions and the reported in situ measurements. We employed a recently developed sliding-window cross-correlation method to locate anticorrelated structures in the solar wind composition measurements between 2001 and 2010 from the Advanced Composition Explorer (ACE). To account for fluctuations and measurement uncertainties, we varied the timescales and temporal lags. We determined the onset and end times of the gradual increases or decreases in the average charge states of O and Fe and analyzed the kinetic and plasma properties of the anticorrelated structures. We identified 103 anticorrelated structures both in the solar wind and in ICMEs. The behavior of $ avQ Fe $ is strongly related to solar wind kinetic properties, including proton speed, proton temperature, and the proton-proton collisional age. We find that the anticorrelation of $ avQ Fe $ and $ avQ O $ during these time periods cannot be explained by differential streaming nor by unrecorded hot plasma ejections. Thus, the measured anticorrelated variations in $ avQ Fe $ and $ avQ O $ probably indicate that changes in coronal conditions at different freeze-in heights may follow opposite monotonic trends.

Associations Between Plasma Levels of NLRP3 Protein, Interleukin-1 Beta and Features of Acute ST-Elevation Myocardial Infarction

Background. Phenotyping inflammation in ST-elevation myocardial infarction (STEMI) is a challenge for modern cardiology. NLRP3 inflammasome is a proven predictor of adverse outcomes in cardiovascular disease, but its specificity in stratifying inflammatory activity in patients with myocardial infarction (MI) has not been demonstrated. The aim of this paper is to describe the levels of NLRP3 protein and IL-1β concentrations and their changes in dynamics and associations with clinical, laboratory and instrumental characteristics of patients with STEMI. Methods. A total of 45 patients with STEMI were enrolled. Concentrations of NLRP3 and IL-1β were evaluated in arterial and venous EDTA blood from the infarct-related coronary and peripheral arteries and veins on days 1, 3 and 7 after MI. Results and Conclusions. The concentrations of markers were higher on the first day after MI with a maximum decrease on the third day. The levels of both markers in venous plasma correlated with those in arterial blood, allowing their routine determination in venous plasma on the first day after MI. IL-1β levels correlated directly with the wall motion index and inversely with left ventricular ejection fraction and stroke volume, which characterize the potential contribution to adverse myocardial remodeling. There were two multidirectional trends in changes in NLRP3 and IL-1β levels during hospitalization. Initially higher levels with a gradual decrease by day 7 were associated with a longer duration of myocardial ischemia and higher plasma troponin I levels. Further evaluation of the long-term outcomes of MI will allow identifying inflammatory factors that input to the development of secondary major adverse cardiac events and will provide a new step in the understanding of inflammatory phenotyping.

Effect of coal quality and preparation on the stamping performance and quality of coke.

This article presents the results of the research on real coal charges of different compositions intended for coking with loading into the chamber by the stamping method. The results of the study established that with an increase in the content of coal at a low stage of metamorphism and a decrease in the content of coal at a high stage of metamorphism in the charges, a decrease in the quality indicators of the coke obtained from them leads to a decrease in the yield of coke. At the same time, there is a gradual decrease in the compaction of the charges from 22.5 to 21.1kPa; their expansion pressure decreases from 6.8 to 5.9kPa; and the work of stamping decreases from 8966 to 6822J. It was also discovered that with the increase in the degree of grinding of the charge, and, accordingly, with the decrease in the average diameter of its particles, the work of stamping coal charges decreases from 7407 to 6238J. The results can be used in the manufacturing of blast furnace coke by stamping coal charges.

Inhibition of the Growth of Four Phytopathogenic Fungi by Eucalyptus Wood Vinegar

Purpose: The objective of this work aimed to assess the wood vinegar (WV) from the carbonization of Eucalyptus wood in the inhibition in vitro of Fusarium sp., Ganoderma sp., Macrophomina sp., and Sclerotium rolfsii. Method: WV was added to a culture medium and poured onto Petri dishes. After, the fungi were picked up in 1-mm disks and placed in the center of each Petri dish. The experimental design had five treatments, T1, T2, T3, T4, and T5, with crescent concentrations of WV, respectively, 0 (control), 5, 10, 15, and 20 mL L-1. The variables evaluated were fungal growth, mycelial growth rate index, and percentage of mycelial growth inhibition. Results and Discussion: A gradual decrease in the mycelial growth, in the mycelial growth rate index, and an increase in the percentage of mycelial growth inhibition were determined for all assessed fungi in the concentration of 20 mL L-1 of WV. Hence, the conclusion was that eucalyptus WV presented fungi-toxic properties over the assessed fungi and the product can be considered as an alternative for the chemical control of the incidence of these pathogens in crops and forest plantations. Research Implications: The use of natural products with fungi toxic properties is becoming important for the control of pathogens that attack crops and forest plantations due to the harmful effects of the conventional fungicides on living organisms and the environment. The search for efficient alternative products is therefore a goal to be reached in the field of phytopathology. Originality/ Value: The use of natural products with fungitoxic properties has been gaining ground in the control of pathogens affecting agricultural and forestry crops. This intensifies the search for natural products that are efficient in the biocontrol of phytopathologies.

THE IMPACT OF EXOGENOUS AND ENDOGENOUS FACTORS ON VASCULAR WALL ELASTICITY AND POTENTIAL CLINICAL EFFECTS (Review Article)

Vascular aging is associated with profound changes in the structural properties of the arterial wall. Arterial hypertension, diabetes mellitus, and chronic kidney disease are the primary determinants of the loss of elasticity and reduced compliance of the vascular wall. Arterial stiffness is a key parameter for assessing the elasticity of the arterial wall and can be easily evaluated using non-invasive methods such as pulse wave velocity. Early assessment of arterial stiffness is critical, as its changes may precede the clinical manifestations of cardiovascular disease. With age, arterial walls become stiffer, leading to an increase in systolic blood pressure and an increased risk of cardiovascular events such as stroke, myocardial infarction, or heart failure. The gradual decrease in vascular elasticity is accompanied by remodeling of their structure, an increase in collagen fibers, and a decrease in elastin, which exacerbates the problem. In addition, the mechanical stress on the vascular wall, which increases with age, worsens its condition, provoking the formation of atherosclerotic plaques. Arterial stiffness, as an important biomarker of vascular aging, is also an indicator of increased cardiovascular risk, independent of other factors such as blood pressure or the presence of comorbidities. Therefore, timely diagnosis of arterial stiffness can help prevent serious complications and adjust treatment for patients at risk. Important are also preventive measures, including a healthy lifestyle, physical activity, and control of the underlying diseases that contribute to the acceleration of vascular aging processes. Moreover, the influence of endogenous and exogenous factors, such as diet, the presence of chronic diseases, and bad habits (in particular, smoking), contribute to the acceleration of these processes. Innovative diagnostic methods, such as magnetic resonance imaging (MRI) or ultrasound, allow detecting these changes at early stages and, accordingly, adapting treatment.

Early evaluation of salt-stress tolerance of new released olive cultivars based on physiological and biomass allocation indicators

The evaluation of salt-tolerant olive tree genotypes released from breeding program has become intrinsic in order to develop sustainable agriculture in these regions. The current study aims to i) evaluate the tolerance of two new released olive cultivars (Zeitoun Ennour and Zeitoun Ennwader), issued from a Tunisian breeding program in comparison with the main olive cultivar ‘Chemlali Sfax’, and ii) identify suitable salt-tolerance indicators for this evaluation. The trial was conducted under controlled conditions in a greenhouse, for six months, and plants were irrigated with half-strength Hoagland nutrient solution containing NaCl at various levels (0, 75, 150 and 225 mM). Vegetative growth, biomass allocation and biochemical parameters were considered for the assessment of salt-tolerant capacity. Results revealed that growth and biomass should be considered as useful indicators for early evaluation method of salt-stress tolerance. ‘Chemlali Sfax’ displayed a gradual significant decrease of vegetative growth with increasing salinity. The reduction of shoot elongation and trunk diameter was most evidently at 150 mM with 43.2 % and 80.8 %, respectively. However, the new released cultivars showed unaffected vegetative growth, despite a slight decrease at the salt level of 225 mM. Moreover, results demonstrated the importance of certain physiological and biochemical indicators such as ions contents. The new released cultivars maintained a high K+/Na+ ratio at moderate salinity then a significant decrease occurred at 150 mM. In conclusion, vegetative growth, biomass allocation and K+/Na+ ratio seemed to be the suitable salt-tolerance indicators for early evaluation. Based on these indicators, ‘Zeitoun Ennour’ seems to be the most salt tolerant genotype and ‘Zeitoun Ennwader’ proves to have a similar salt tolerant capacity as ‘Chemlali Sfax’, which is a valuable information for olive growers in arid region.

The association between stress hyperglycemia ratio and clinical outcomes in patients with sepsis-associated acute kidney injury: a secondary analysis of the MIMIC-IV database

BackgroundThe stress hyperglycemia ratio (SHR) is associated with poor outcomes in critically ill patients. However, the relationship between SHR and mortality in patients with sepsis-associated acute kidney injury (SA-AKI) remains unclear.MethodsThe data of patients with SA-AKI, identified based on the KDIGO criteria, were retrospectively collected from the Beth Israel Deaconess Medical Center between 2008 and 2019. SHR was calculated as follows: (glycemia [mmol/L]) / (1.59 × HbA1c [%] – 2.59). Primary outcomes were 30-day and 1-year mortality. The cumulative incidence of all-cause mortality was assessed using Kaplan–Meier survival analysis. Multivariable-adjusted logistic and Cox models and restricted cubic spline curves were used to analyze the correlation between SHR and all-cause mortality. Post-hoc subgroup analysis was performed to compare the effects of SHR across different subgroups.Results1161 patients with SA-AKI were identified and categorized into four SHR quartiles as follows: Q1 (0.26, 0.90), Q2 (0.91, 1.08), Q3 (1.09, 1.30), and Q4 (1.31, 5.42). The median age of patients was 69 years, with 42.7% of the patients being women and 20.2% of the patients having chronic kidney disease. The 30-day and 1-year mortality were 22.1% and 35.0% respectively. Kaplan–Meier survival analysis indicated a gradual decrease in survival probability with increasing SHR quartiles. An increased SHR exhibited a strong correlation with 30-day mortality (hazard ratio [HR], 1.50; 95% confidence interval [CI], 1.18–1.90; P < 0.001) and 1-year mortality (HR, 1.32; 95% CI, 1.06–1.65; P = 0.014). SHR has a nonlinear relationship with 1-year mortality but not with 30-day mortality (P-nonlinear = 0.048 and 0.114, respectively). The results of subgroup analysis were mostly consistent with these findings.ConclusionAn increased SHR is independently associated with 30-day and 1-year mortality in patients with SA-AKI. Therefore, SHR may serve as an effective tool for risk stratification in patients with SA-AKI.

GABA Prevents Sarcopenia by Regulation of Muscle Protein Degradation and Inflammaging in 23- to 25-Month-Old Female Mice.

Sarcopenia is the gradual decrease in skeletal muscle mass, strength and function in elderly individuals. Gamma-aminobutyric acid (GABA) is a neurotransmitter naturally produced from glutamate by the enzyme glutamic acid decarboxylase. Age-related decline in GABA is linked to age-related motor and sensory decline and seems to affect sarcopenia, yet no detailed study has been conducted. In this study, we aimed to investigate the effect of GABA on improving sarcopenia by suppressing muscle protein degradation through supplementing decreased GABA in old mice. GABA (10 or 30 mg/kg/day) was orally administered daily to young (3 months) and old (21-23 months) C57BL/6 mice for 7 weeks. The body weight and grip strength of the mice were measured weekly at the same time. After sacrificing the mice, the quadriceps and gastrocnemius muscles were excised from their hind limbs, and the spleen and serum were collected. Histological, biochemical and molecular analyses were conducted in various experiments. The administration of GABA increased muscle strength (+41%, +70% compared to the aged mouse control group, GABA at doses of 10 or 30 mg/kg/day respectively, p < 0.05) and muscle mass (quadriceps: +28%, +46%; gastrocnemius: +12%, +19%, p < 0.05) in old mice. This increase was accompanied by a cross-sectional area (CSA) increase in the quadriceps and gastrocnemius muscle (p < 0.05). The administration of GABA increased IGF-1 levels in serum (p < 0.05), leading to the activation of muscle protein synthesis. We found that GABA inhibits sarcopenia by regulating muscle protein degradation through the activation of Akt/mTOR/FoxO3a signalling pathways. GABA also regulates inflammaging, which is a hallmark of age-related muscle atrophy. There was a significant increase in the F4/80 + CD11b + total macrophage ratio in gastrocnemius and spleen, especially the M1 macrophage ratio increased in old mice. However, GABA administration was effective in suppressing M1 macrophages (gastrocnemius: -40%, - 53%; spleen: -22%, -26%, p < 0.05). Pro-inflammatory cytokines such as TNF-α and IL-6, primarily secreted by M1 macrophages, are also decreased by treatment with GABA (TNF-α: -24%, -27%; IL-6: -45%, -59%, p < 0.05). Together, this study demonstrates the importance of GABA in maintaining muscle and low-chronic inflammation during ageing. We suggest that GABA shows potential as a substance that can effectively address sarcopenia and enhance the overall lifespan and well-being of older individuals.

Unraveling Microviscosity Changes Induced in Cancer Cells by Photodynamic Therapy with Targeted Genetically Encoded Photosensitizer

Background: Despite the fundamental importance of cell membrane microviscosity, changes in this biophysical parameter of membranes during photodynamic therapy (PDT) have not been fully understood. Methods: In this work, changes in the microviscosity of membranes of live HeLa Kyoto tumor cells were studied during PDT with KillerRed, a genetically encoded photosensitizer, in different cellular localizations. Membrane microviscosity was visualized using fluorescence lifetime imaging microscopy (FLIM) with a viscosity-sensitive BODIPY2 rotor. Results: Depending on the localization of the phototoxic protein, different effects on membrane microviscosity were observed. With nuclear localization of KillerRed, a gradual decrease in microviscosity was detected throughout the entire observation period, while for membrane localization of KillerRed, a dramatic increase in microviscosity was observed in the first minutes after PDT, and then a significant decrease at later stages of monitoring. The obtained data on cell monolayers are in good agreement with the data obtained for 3D tumor spheroids. Conclusions: These results indicate the involvement of membrane microviscosity in the response of tumor cells to PDT, which strongly depends on the localization of reactive oxygen species attack via targeting of a genetically encoded photosensitizer.

Degradation of Argan Oils Used in Edible and Cosmetic Applications After Exposure to UV Light.

This study investigates for the first time the effects of UV light exposure on the chemical composition of artisanal and cold-pressed culinary and cosmetic argan oils, as well as their quality and biological activities. We ascertained the oxidative stability of both types of oil through measurements of the peroxide value, acidity, UV-spectrophotometric indexes (E232 and E270), and iodine value. Over the course of eight hours at room temperature, the impact of UV light on the breakdown of tocopherols, polyphenols, chlorophylls, and carotenoid pigments was examined. The findings showed that during photo-oxidation, acidity, peroxide value, and particular extinction coefficients (E232 and E270) gradually increased. On the other hand, a decline in the content of polyphenols, tocopherols, carotenoid, and chlorophyll was noted. Interestingly, iodine levels failed to improve. Although after an eight-hour degradation, the physicochemical profile of Argan oils remained exceptional. DPPH• (1,1-Diphenyl-2-picrylhydrazyl) antioxidant activity tests showed a gradual decrease in radical inhibition over time, which was attributed to lower levels of tocopherol and polyphenol. However, roasted oils showed antifungal action against Botrytis cinerea fungus, while Argan vegetable oils showed no activity against Escherichia coli, Microbacterium resistens, Staphylococcus saprophyticus, and Raoultella ornithinolytica, according to antimicrobial assays.

STRESS ANALYSIS OF THE MAIN COMPONENTS OF IMPROVED GATE VALVE CONSTRUCTION

This study explores the stress resistance of an improved valve design under high-pressure conditions, focusing on stress distribution across both the sealing element and the valve body. A 2D model of the valve was created in AutoCAD and analyzed using Python’s Matplotlib, simulating performance under pressures up to 75 MPa, 5 MPa above the operational limit. Results reveal critical stress patterns, with stress concentrations reaching up to 325 MPa along the inner radius of the sealing element and valve body. Radial, longitudinal, and circumferential stresses were evaluated, showing a gradual decrease in compressive forces from the inner to outer surfaces. The contact areas between the sealing element and valve body emerged as critical zones, with high-pressure exposure raising the risk of early material fatigue and functional degradation. Overall, the improved valve design exhibits significant resilience under high-pressure conditions. However, sustaining this performance over time will require proactive inspection and maintenance to prevent premature wear and material fatigue. This research provides valuable insights for enhancing valve designs and improving durability in high-pressure applications within the oil and gas industry. The analysis demonstrates that the improved valve design can withstand high pressures effectively, but highlights the importance of routine inspection and maintenance to prevent premature failure due to material fatigue. Continuous monitoring, particularly around the inner radius and critical contact areas, is recommended to ensure operational longevity and reliability under fluctuating pressure conditions. Keywords: Linear motion valve, body, finite element analysis, wear, seal.

Indium-Iron Oxide Nanosized Solid Solutions as Photocatalysts for the Degradation of Pollutants under Visible Radiation.

A series of solid solutions of indium and iron oxides with different In/Fe ratios (InxFeyO3, with x + y = 2) were synthesized in the form of nanoparticles (diameter of ca. 30-40 nm) with the purpose of generating enhanced photocatalysts with an intermediate band gap compared to those of the monometallic oxides, In2O3 and Fe2O3. The materials were prepared by co-precipitation from an aqueous solution of iron and indium nitrates and extensively characterized with a combination of techniques. XRD analysis proved the formation of the desired InxFeyO3 solid solutions for Fe content in the range 5-25 mol%. UV-Vis absorption analysis showed that the substitution of In with Fe in the crystalline structure led to the anticipated gradual decrease of the band gap values compared to In2O3. The obtained semiconductors were tested as photocatalysts for the degradation of model organic pollutants (phenol and methylene blue) in water. Among the InxFeyO3 solid solutions, In1.7Fe0.3O3 displayed the highest photocatalytic activity in the degradation of the selected probe molecules under UV and visible radiation. Remarkably, In1.7Fe0.3O3 showed a significantly enhanced activity under visible light compared to monometallic indium oxide and iron oxide, and to the benchmark TiO2 P25. This demonstrates that our strategy consisting in engineering the band gap by tuning the composition of InxFeyO3 solid solutions was successful in improving the photocatalytic performance under visible light. Additionally, In1.7Fe0.3O3 fully retained its photocatalytic activity upon reuse in four consecutive cycles.

MINERALOGICAL, PETROGRAPHIC, AND LITHOCHEMICAL FEATURES OF THE UPPER JURASSIC–LOWER CRETACEOUS SECTION OF THE NORDVIK PENINSULA (NORTH OF EASTERN SIBERIA)

Some intervals of the Jurassic–Cretaceous strata of the Anabar-Lena sedimentary basin have a certain oil and gas production potential, which can be realized in the synchronous offshore horizons of the adjacent territories of the Arctic shelf. Among the most representative objects in this regard are the outcrops of Upper Jurassic and Lower Cretaceous formations of the Nordvik Peninsula. The main data on the composition and structure of this section were obtained mainly at the beginning of the second half of last century. The results of complex mineralogical, petrographic, and lithochemical studies of the Urdyuk-Khaya and Paksa formations of Cape Urdyuk-Khaya of the Nordvik Peninsula presented in here enabled us to identify 10 boundaries for changing of sedimentation regimes of the paleobasin. It was found that the Urdyuk-Khaya Formation was formed mainly in the conditions of the shelf transition zone (moderate deep water) with low rates of terrigenous material intake, some depletion of oxygen in bottom waters, and a trend towards an increase in the depths of the basin. The basal stratum of the Paksa Formation was formed in offshore conditions with periodically occurring dioxic conditions in bottom waters and extremely low rates of terrigenous material intake. The overlying part of the formation was formed in various parts of offshore transition conditions with a gradual decrease in the depths of the basin, an increase in the oxygen content in the bottom layer of water, and the rate of terrigenous material intake. The main provenance area was igneous rocks of mafic, possibly intermediate composition. There was some influence of felsic igneous rocks, or ancient sedimentary rocks rich in quartz. The parent strata were subjected to moderate and severe chemical weathering, in a warm humid climate. The revealed features of the studied strata are similar to the characteristics of the same-age sediments of the lower reaches of the Anabar River, which determines their high correlation potential and allows us to judge the evolution of the western part of the Anabar-Lena basin.