Loss In Resistance Research Articles

Ecological mortars produced from sustainable hydrated lime obtained from biomass ash

Sustainable hydrated lime is produced from biomass ash rich in calcium carbonate, with properties similar to industrial hydrated lime. However, there is a lack of current and relevant research on sustainability related to the use of alternative limestone, derived from waste such as biomass ash. In this sense, the present research aims to study the behavior of cementitious coating mortars with partial and total replacement of industrial hydrated lime by sustainable hydrated lime, through microstructural, macrostructural, physical and chemical tests. Microstructural analyses performed by SEM demonstrated the presence of cement hydration products (CSH and ettringite) in all mortars evaluated. Chemical analyses through XRF and XRD showed similarity in chemical composition and crystallographic phases between the mortar with industrial hydrated lime and the ecological mortars. The FTIR showed chemical bonds characteristic of cement mortars in all ecological mortars, ratified by TG/DTG, which shows the decomposition of products such as CSH, ettringite, portlandite and calcite in all ecological mortars. Through the results found, the viability of replacing sustainable hydrated lime with industrial hydrated lime in the preparation of ecological mortars stands out, at the optimum percentage of 50 %, with possible total replacement (100 %) without significant losses in resistance.

Oxidation resistance and thermal stability of (MoZrHfTaNb)-Si-B coatings deposited by HIPIMS method with different Ar pressure

The influence of argon pressure on the structure, mechanical characteristics, oxidation resistance, and thermal stability of (MoTaNbZrHf)-Si-B coatings deposited by HIPIMS method using a composite target based on high-entropy (MoZrHfTaNb)Si2 silicide and (MoZrHfTaNb)B2 boride was studied. Coatings deposited at Ar pressure of 0.1–0.2 and 1.3–2.2 Pa had a dense, defect-free structure. Increasing the Ar pressure to 37–42 Pa led to the formation of a coating with a columnar structure, while, according to X-ray diffraction and transmission electron microscopy, all coatings were amorphous. Increasing the Ar pressure from 0.1 to 0.2 to 37–42 Pa led to a magnifying the growth rate of coatings in 2.5 times. All coatings were characterized by a similar hardness of 14–15 GPa. The elastic modulus and elastic recovery decreased from 196 to 178 GPa and from 40 to 34 % when the argon pressure increased from 0.1 to 0.2 to 37–42 Pa, respectively. The coatings successfully resisted oxidation at temperatures of 1100 °C and 1300 °C. The protective properties of the coatings are due to the formation of a dense oxide film based on a-Si:B:O amorphous phase with crystallites of the m-HfO2, m-ZrO2, m-Nb2O3, o-Ta2O5, t-ZrSiO4 and t-HfSiO4 phases. Heating in a TEM column showed that the coating deposited at an Ar pressure of 0.1–0.2 Pa crystallizes immediately upon reaching a temperature of 700 °C with the release of predominantly the h-MoSi2 phase. Crystallization of the coating obtained at an Ar pressure of 37–42 Pa also occurs at 700 °C, but only during long-term exposure and is accompanied by the precipitation of the h-Ta5Si3 and t-Nb5Si3 phases. Thus, it has been shown that by increasing the gas flow rate, the productivity of sputtering in the HIPIMS mode can be increased without a significant loss in hardness, oxidation resistance and thermal stability of coatings.

Dose-dependent effects of gamma radiation sterilization on the collagen matrix of human cortical bone allograft and its influence on fatigue crack propagation resistance

Fatigue crack propagation resistance and high-cycle S–N fatigue life of cortical bone allograft tissue are both negatively impacted in a radiation dose-dependent manner from 0 to 25 kGy. The standard radiation sterilization dose of 25–35 kGy has been shown to induce cleavage of collagen molecules into smaller peptides and accumulation of stable crosslinks within the collagen matrix, suggesting that these mechanisms may influence radiation-induced losses in cyclic fracture resistance. The objective of this study was to determine the radiation dose-dependency of collagen chain fragmentation and crosslink accumulation within the dose range of 0–25 kGy. Previously, cortical bone compact tension specimens from two donor femoral pairs were divided into four treatment groups (0 kGy, 10 kGy, 17.5 kGy, and 25 kGy) and underwent cyclic loading fatigue crack propagation testing. Following fatigue testing, collagen was isolated from one compact tension specimen in each treatment group from both donors. Radiation-induced collagen chain fragmentation was assessed using SDS-PAGE (n = 5), and accumulation of pentosidine, pyridinoline, and non-specific advanced glycation end products were assessed using a fluorometric assay (n = 4). Collagen chain fragmentation increased progressively in a dose-dependent manner (p < 0.001). Crosslink accumulation at all radiation dose levels increased relative to the 0 kGy control but did not demonstrate dose-dependency (p < 0.001). Taken together with our previous findings on fatigue crack propagation behavior, these data suggest that while collagen crosslink accumulation may contribute to reduced notched fatigue behavior with irradiation, dose-dependent losses in fatigue crack propagation resistance are mainly influenced by radiation-induced chain fragmentation.

Investigation of the structural stability of polycrystalline cBN under near-industrial grinding process conditions

Cubic boron nitride (cBN) is an important material in the cutting and metal processing industries due to its exceptional hardness and high thermal stability, which allows it to withstand temperatures up to 1400 °C without decomposing. These properties make cBN and, with that, polycrystalline cBN (PcBN) ideal materials for high-speed machining and other applications, resulting in increased efficiency and reduced costs in production processes. Despite its established importance, the possibility of phase transformations into hexagonal boron nitride phases or partial amorphization during industrial PcBN grinding processes remains unclear and, due to the deteriorated mechanical characteristics, raised recently some concerns about possible losses of cBN's hardness, wear resistance, and abrasive properties. In order to address this issue and for identifying such potential structural changes, a commercial PcBN grade was exposed to near-industrial grinding process conditions and then characterized in detail by conventional (scanning) transmission electron microscopy (S)TEM and (scanning) electron diffraction techniques. To understand the influence of the PcBN machining on the material, the grinding process also needs to be assessed via the identification of chip formation mechanisms, which is as well addressed in this work. The main outcome of this study, combining a material analysis and a manufacturing technology point of view, is that there is so far no evidence of any structural instabilities of PcBN under usual processing conditions.

Low tortuous permeable concrete pavement material: A new approach to improve physical properties

Permeable pavement is an environmentally beneficial material that can ease urban problems and mitigate the effects of climate change, such as flooding, urban heat islands, and groundwater decrease. However, it is susceptible to clogging, has limited strength, and demands frequent maintenance. To overcome these problems, an untraditional fiber-reinforced permeable pavement with a low tortuosity pore structure that has an excellent infiltration rate and strength while being resistant to clogging has been studied in this research. Straight pore channels of various sizes and quantities were introduced into self-compacting concrete to create this permeable pavement. High-strength pervious pavement (HSP) samples with porosity ranging from 3.60 to 8.30% and 0–0.2% fiber content were tested. In all cases, HSP showed high infiltration rate (>1 cm/s), high compressive strength (>27 MPa) and tensile strength (1.5 MPa), low mass loss in potential resistance to degradation by impact and abrasion (>25%). However, it did not clog despite extensive cyclic exposure to flow containing sand, clay, and combined ‘sand & clay’. PP fiber content of 0.1%. The 3.60% porosity was found to be optimum considering all properties, whereas 8.30% porosity gave a higher infiltration rate with compromised properties. This permeable pavement can maintain sufficient porosity and permeability for stormwater infiltration without frequent maintenance. Adding polypropylene fiber reduces compressive strength marginally but increases split tensile strength, degradation and potential resistance. This novel fiber-reinforced HSP has the potential to expand the material's applicability. The results obtained from this research are expected to lead the way for a broader application of HSP in various contexts and initiatives that were not previously considered appropriate. This will eventually enhance the design and implementation of a new generation of flood-resistant infrastructure and significantly improve the ability to mitigate urban floods.

Impact of Hair Damage on the Penetration Profile of Coconut, Avocado, and Argan Oils into Caucasian Hair Fibers

The mitigation of damaged hair conditions involves the application and penetration of substances to stabilize broken bond sites, restore lipids and proteins, reinstate hydrophobicity, and recover hair mechanical properties. Vegetable oils, in general, exhibit a list of advantageous characteristics much desired by consumers, given the associated benefits for hair fibers. While coconut oil is highly popular in the hair care market and extensively studied for its ability to diffuse through the hair cortex, the effects of avocado and argan oil on the internal structure of hair and their potential benefits remain underexplored. Tensile and fatigue tests, as well as Raman spectroscopy, were carried out to investigate the interaction of these three oils with virgin and bleached Caucasian hair. The oils were applied in sufficient amounts directly to hair tresses and maintained for 24 h at 25 °C. Our results show that the three oils successfully diffused and interacted with the cortical region of the hairs. Their impact on hair mechanical properties depends on the level of damage and humidity conditions. In virgin hair, coconut and avocado oil reinforce the hydrophobic barrier of the cellular membrane complex, preventing water from causing intense perturbation of the mechanical properties, leading to increased stiffness and break stress. Meanwhile, due to the high degree of unsaturation of its fatty acid chains, argan oil increases water absorption, resulting in losses in hair resistance. When bleached, the hydrophilicity of the hair fiber increases, determining more affinity for argan oil. Consequently, the affinity with water is also elevated, causing increased fragility to mechanical stress. The analyzed vegetable oils are not always beneficial for hair care. Their specific chemical characteristics and hair conditions will influence the final results and should be taken into consideration in hair care product development.

Sustainable Composites: Analysis of Filler-Rubber Interaction in Natural Rubber-Styrene-Butadiene Rubber/Polyurethane Composites Using the Lorenz-Park Method and Scanning Electron Microscopy.

This study examined micronized polyurethane residues as a reinforcing filler in elastomeric composites made from natural rubber (NR) and styrene-butadiene rubber (SBR). Due to growing environmental concerns, this research aimed to find sustainable alternatives to synthetic materials. The results indicated that adding micronized polyurethane improved the mechanical properties of the composites, reinforcing the polymer matrix and increasing the cross-link density as a barrier against solvents. The composites met the requirements for industrial applications, though; at 40 phr of polyurethane filler, material deformation was reduced, indicating saturation. FTIR analysis confirmed the homogeneity of the materials without chemical reactions, while electron microscopy revealed an increase in the number of particles and irregularities with the filler. The composite with 10 phr showed a lower volume loss in abrasion resistance, meeting the standards for soles. The composite with 30 phr of polyurethane achieved the best results without the filler's saturation and met the footwear industry's requirements. The results show the potential for sustainable practices in industry using this elastomeric blend.

Optimization of the Mechanical and Corrosion Resistance of Alloy 625 through Aging Treatments

In the as-annealed condition, the nickel-based Alloy 625 has excellent mechanical and corrosion properties compared to those of common stainless steels. This peculiarity enables its exploitation in several industrial fields at cryogenic and high temperatures and in the presence of severely corrosive atmospheres. However, in this alloy, when high-temperature plastic deformation processes and heat treatments are not carefully optimized, the occurrence of excessive grain coarsening can irremediably deteriorate the mechanical strength, possibly leading to incompatibility with the standard requirements. Therefore, this research work investigated the possibility of adopting single- and double-aging treatments aimed at improving such strength loss. Their optimization involved identifying the best compromise between the hardening effect and the loss in corrosion resistance induced by the simultaneous formation of intergranular chromium-rich carbides during aging. The investigation of the aging treatments was performed using hardness, tensile and intergranular corrosion tests considering different time–temperature combinations in a range from 621 °C to 732 °C. Double aging resulted in a considerable acceleration in the hardening response compared to single aging. However, even after its optimization in terms of both temperature and time, the intergranular corrosion resistance remained a critical aspect. Among all the tested conditions, only single aging at 621 °C for 72 h was acceptable in terms of both mechanical and corrosion properties. The influence of longer exposures will be investigated in a future study.

Neutron Nanomediators for Non-Invasive Temperature Mapping of Fuel Cells

Polymer electrolyte fuel cells (PEFCs) have gained significant attention in the past century for their ability to convert hydrogen chemical energy into electrical energy. However, the technology still requires refinement due to losses in polarization, ohmic resistance, and mass transport that result in heat generation, negatively affecting the device water management and durability. To better understand these processes, researchers initiate studies to improve knowledge of the temperature at the cell structure core. However, current methods using micro-thermocouples [1] are highly invasive, impeding cell operation and limiting data accuracy.The project aims to overcome the latter problem using ferromagnetic nanoparticles for non-invasive temperature mapping on these devices. A key part of this novel method is the application of Neutron Imaging through a polarized beam [2], which allows to detection of the temperature distribution on the surrounding nanosensors. The dispersed ferromagnetic nanomediators, in these conditions, depolarize the incoming neutron beam due to the random magnetic field produced by the nanoparticles themselves. Furthermore, as the temperature rises toward the Curie temperature (Tc), the nanosensors tend to lose their magnetic preferential orientation, influencing the neutron beam polarization gradually less as the ambient temperature increases.This project includes identifying a suitable material, synthesizing nanoparticles through solution techniques [3], and performing physical and magnetic ex-situ characterizations. By dispersing them in Polytetrafluoroethylene micro-powders, nickel, iron, and Nd2Fe14B alloys were initially studied at different concentrations, grain sizes, and magnetic environments, showing promising signal detection (η) and absolute thermal variation (Δη) results.

Carbonation resistance of sustainable self-compacting concrete with recycled concrete aggregate and fly ash, slag, and silica fume

This study focused on the problem of recycling construction and demolition wastes as well as industrial waste by-products into sustainable concrete materials. By combining addition of three different industrial waste by-products, an environmentally friendly recycled aggregate self-compacting concrete (RA-SCC) mix was put forward. Carbonation resistance and microstructure of SCC incorporating high volumes of industry by-products and recycled aggregates were studied in this paper. A total of 9 RA-SCC with 50%, 75% supplementary cementitious materials (SCMs) and different SCM combinations were prepared, which consist of binary mix with fly ash (FA), ternary mix with FA and ground granulated blast-furnace slag (GGBS), and quaternary mix with FA, GGBS, and silica fume (SF). An exposure period of 3, 7, 14, and 28 days was adopted for accelerated carbonation tests. The test results indicate that, as RCAs content increased, RA-SCC carbonation depth increased. The carbonation depth of SCC with 100% RCAs increased by 49.35% compared to that of normal SCC. In addition, carbonation resistance of RA-SCC mixes with a given compressive strength decreased with increasing SCM content. However, the loss in carbonation resistance was greatly mitigated by the combined addition of different SCMs, on account of the substitution of cement with industrial by-products and natural aggregates with RCAs. The combined addition of different SCMs enhanced the carbonation resistance of RA-SCC mixes. The test results were validated through microstructural analysis using scanning electron microscopy (SEM), and X-ray diffraction (XRD). A comparison between predictions calculated using existing models and measured carbonation depth was implemented. By taking into account the effect of RCAs and SCMs, a modified carbonation model in conjunction with fib carbonation model was put forward.

Q-Carbon as a Corrosion-Resistant Coating.

A newly discovered quenched form of carbon, widely known as Q-carbon, thin films are synthesized by the direct conversion of the amorphous carbon layer using the nanosecond pulsed laser annealing technique, and its corrosion-resistant properties, that is, potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy technique, are investigated. The unique microstructure and the existence of defects (sp2 content) in sp3-rich Q-carbon are highly desirable for efficient corrosion-resistant performance. The sp3 percentage of the as-grown Q-carbon is measured to be ∼80.5% from the D and G peaks of the Raman and C-1S X-ray photoelectron spectrum. The anti-corrosion properties with inhibition durability of Q-carbon thin films are systematically investigated in various concentrations of Na2SO4 solutions, and the corrosion potential, corrosion current, and corrosion rate of Q-carbon are determined to be -253 V, 30.1 × 10-5 A/cm2, and 0.00528, respectively, for 1 M Na2SO4 solution. Both series and contact resistance decrease from 5498.6 and 821.1 Ω to 698.8 and 124.3 Ω with an increase of Na2SO4 concentration from 0.1 to 1 M, respectively. The small shift of PDP curves toward more negative potential, the shrinkage of the radius of semicircular arcs in the Nyquist plot (Z″ vs Z'), and negligible loss in corrosion resistance (∼78%) are observed for Q-carbon thin film at the immersion time up to 48 h. The unique sp2-sp3 ratio, shorter bond length, compact atomic arrangement, and minimum porosity, along with the high adhesion strength, due to the ultrafast solid-liquid-solid growth route, of Q-carbon thin film on the substrate signify it as a better alternative compared to the existing corrosion-resistant materials.

Introducing the grafted poly(acrylic acid-co-butyl acrylate) branches onto biological corn starch macromolecule for imparting it with superior sizing properties

The objective of this study was to survey the influence of poly(acrylic acid-co-butyl acrylate) [P(AA-co-BA)] branches on the sizing properties (i.e., paste stability, adhesion, properties of film and sized warps) of biological macromolecule (corn starch) for further promoting the properties of bromoisobutyryl esterified starch (BBES) and developing a new biobased sizing agent [BBES-g-P(AA-co-BA)]. The sizing properties of BBES-g-P(AA-co-BA) were estimated in comparison with acid-hydrolyzed starch (AHS) and BBES. Compared with the two starches, BBES-g-P(AA-co-BA) displayed higher paste stability, bonding forces to both polyester and polyester/cotton roving, film elongation and water solubility, as well as lower film strength. And the increased grafting ratio exhibited positive effects on these properties of BBES-g-P(AA-co-BA). The properties containing increase in strength, loss in extension, abrasion resistance and hairiness of polyester and polyester/cotton blended yarns sized with BBES-g-P(AA-co-BA), were superior to those sized with AHS and BBES, respectively, indicating that the incorporation of P(AA-co-BA) branches onto BBES could further promote the sizing qualities of both yarns. The BBES-g-P(AA-co-BA) with a grafting ratio of 16.51 % was concluded to size both yarns for improvement of yarn quality.

The Effects of Ketogenic Diet on Insulin Sensitivity and Weight Loss, Which Came First: The Chicken or the Egg?

The ketogenic diet (KD) is, nowadays, considered an interesting nutritional approach for weight loss and improvement in insulin resistance. Nevertheless, most of the studies available in the literature do not allow a clear distinction between its effects on insulin sensitivity per se, and the effects of weight loss induced by KDs on insulin sensitivity. In this review, we discuss the scientific evidence on the direct and weight loss mediated effects of KDs on glycemic status in humans, describing the KD's biochemical background and the underlying mechanisms.

Effect of Transoral Outlet Reduction on Hepatic Fibrosis in Roux-en-Y Gastric Bypass Patients with Weight Regain and Non-alcoholic Fatty Liver Disease.

Weight regain after Roux-en-Y gastric bypass (RYGB) is associated with worsening of liver outcomes. However, the effect of transoral outlet reduction (TORe) on liver fibrosis in RYGB patients with weight regain and possible advanced fibrosis remains unknown. This was a retrospective analysis of prospectively collected data of RYGB patients who underwent TORe for weight regain. Only patients with possible advanced fibrosis were included. TORe was performed using either an endoscopic suturing device (S-TORe) or plication device (P-TORe) to reduce the gastrojejunal anastomosis (GJA) and pouch sizes. Primary outcomes included changes in non-invasive tests (NITs) for fibrosis at 6-12months. Secondary outcomes included weight loss and changes in insulin resistance and lipid profile at 6-12months. Fifty RYGB patients were included. Baseline age and BMI were 55 ± 11years and 40.1 ± 7.3kg/m2. Baseline GJA and pouch sizes were 20 ± 7mm and 5 ± 2cm, respectively. Thirty patients (60%) underwent S-TORe and 20 patients (40%) underwent P-TORe. At 12months following TORe, there were statistically significant improvements in NITs for fibrosis, including ALT, AST and FIB-4. There was a trend towards significant improvement in liver stiffness measurement on transient elastography. Patients experienced 8.8 ± 11.2% total weight loss (TWL) (p < 0.0001), with 60% experiencing at least 10% TWL. Additionally, there was a significant improvement in HbA1c and a trend toward significant improvement in Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), suggestive of improved insulin sensitivity. TORe is associated with an improvement in hepatic fibrosis in patients with NAFLD and possible advanced fibrosis.

Frequency Response Extension of a Pulsed Magnetic Field Meter Based on an RL Integrator

Introduction. Measurements of the amplitude-time characteristics of pulsed magnetic fields are required in various research and technology areas. Such measurements are carried out during pulsed magnetic field immunity testing, with the magnetic field pulse rise time being hundreds of ns, and the pulse duration to its half initial value (halfdroop) being hundreds of µs.Aim. To develop a meter of magnetic field strength with a linear conversion characteristic for measuring the pulse rise time, the pulse duration to its half-droop, and the peak value of the pulsed magnetic field strength.Materials and methods. Among several available methods for measuring pulsed magnetic field parameters, the induction method was selected. To obtain a signal proportional to the pulsed magnetic field strength, a signal from the induction transducer is integrated using a self-integrating induction transducer (RL integration) or by using an external RC integrator. The former method shows good results when measuring signals with a duration of hundreds of ns; however, this method is inefficient when measuring the parameters of longer-duration pulses. The latter method is used to determine the parameters of signals with a duration of hundreds of µs and ms; however, this method gives a large error when measuring the parameters of signals with a duration of hundreds of ns and less. The consecutive use of the two integration methods leads to an additional error in the measurement of the pulse duration to its half-drop.Results. A setup for determining the required magnetic field pulse parameters using a pulse magnetic field meter based on an RL integrator was developed. The relative measurement errors comprised 10, 10, and 9 %, respectively. The developed setup eliminates the error caused by losses in the active resistance of an induction transducer, thus enabling the pulse duration to its half-droop to be measured without additional errors under the pulse rise time of hundreds of ns and the pulse droop time of hundreds of µs.Conclusion. The development of a functional converter made it possible to extend the frequency response of a pulsed magnetic field meter based on an RL integrator to the low-frequency region.

Studies of nano-SiO2 and subsequent water curing on enhancing the frost resistance of autoclaved PHC pipe pile concrete

Autoclave curing will cause severe deterioration on the frost resistance of pre-stressed high-strength concrete (PHC) pipe pile. To clarify the frost resistance degradation mechanism of autoclaved PHC pipe pile concrete and obtain effective improvement measures, nano-SiO2 (NS) with cement replacement ratios of 0.5%, 1.0%, and 1.5% were adopted, and concrete specimens were fabricated and subjected to standard curing, autoclave curing, and autoclave curing + one week of subsequent water curing, respectively. Then, a rapid freeze-thaw cycle experiment was utilized to test their frost resistance. In addition, the micro-morphology and pore structure of different concrete were studied through scanning electron microscopy and nuclear magnetic resonance. The results indicate that the mechanisms of the degradation of autoclaved concrete in frost resistance are the increase of concrete porosity, harmful pore ratio, and concrete brittleness. Compared with standard curing, autoclave curing can result in 68.5% loss in the frost resistance of concrete. Through playing the filling and pozzolanic effects, NS can improve the compactness of autoclaved concrete and increase its frost resistance to a certain extent. Subsequent water curing can replenish water into concrete, promote the hydration of the residual unhydrated cementitious materials in concrete, enhance the compactness of concrete, and play a positive role in improving the frost resistance of concrete. The incorporation of 1.0% NS can enhance the frost resistance of autoclaved concrete by 66.6%, while the combination of 1.0% NS incorporation and one-week subsequent water curing can enhance the frost resistance by 89.2%. Exponential function can be used to simulate the frost resistance degradation of the autoclaved PHC pipe pile and predict its service life based on frost resistance.

Nocardia seriolae cell wall lipids: An effective protective mechanism in resistance and virulence.

Piscine nocardiosis, caused by Nocardia seriolae, is a refractory granulomatous disease in South-East Asian aquaculture. This study investigates the virulence of nocardial lipids essential for pathogenesis among Actinomycetes. Petroleum ether (PE) was used to selectively delipidate two groups of N.seriolae, namely, live cell (LC) and killed cell (KC); resulting in delipidated live cell (DLC) and delipidated killed cell (DKC), respectively. Changes post-delipidation on genus characteristics, such as loss in acid-fast nature and resistance to lysozyme were observed. Transmission electron microscopy revealed notable changes in the lipid layer. Additionally, Lates calcarifer, Asian seabass intraperitoneally injected with LC and DLC had mortality rates of 90% and 50%, respectively, with the latter exhibiting a delay in mortality. Reverse-transcription quantitative PCR (RT-qPCR) analysis of host cytokines from the spleen and head kidney showed delipidation contributed to the induction of an immune response with increased transcriptional levels of interferon-γ (ifn-γ). Histopathological samples collected on day 7 post-inoculation displayed a varied granulomatous response between the treatment groups and scored for pathological changes. These findings affirm that the virulence of the lipids remains independent of the living state of the cell, significantly altering the immune and granulomatous responses in L.calcarifer to N.seriolae.

РЕЛІГІЙНІ ОБРАЗИ У ВІЗУАЛЬНОМУ ПОЛІ ВІЙНИ: НОВІ РЕФЕРЕНЦІЇ ДО ТРАДИЦІЇ

The paper looks at the works of modern Ukrainian graphics (both printed and digital), which dealt with the events of the war in Ukraine from 2022 onwards. It focuses on the artworks, which use Christian symbolism and iconography and looks at how these symbols were reinterpreted in the context of modern visual culture and the current expectations of Ukrainian society. The study is structured around the categories of cultural memory and representation, in particular the visual and narrative strategies when dealing with the wartime events. It, too, is informed by approaches of visual studies, developed in the works of W.T.J. Mitchell, D. Freedberg, and T. Wright, which helped to determine the primary message of the artworks, secondary elements, and to treat them as a very specific visual message. To systematise the graphic material collected after the full scale invasion 2022, a topical approach was chosen, which means that the focus was not on the chronology of the war, but on the crucial categories in the subject matter of the religious imagery: images of the Mother of God, holy warriors, motifs of the Passions, martyrology, etc. The artworks in question demonstrated a shift from conventional patterns of religious iconography to updated ones. For example, the theme of Christ’s Passion and the tools for torture was altered to become an image of Ukraine's suffering in the course of history with all the struggles and losses of political independence and constant resistance through these centuries. Obviously, the photos and videos from the war omnipresent in the mass and social media became an important visual basis for most graphic works. The article reveals the process of transforming the local war narrative into a universal one, by virtue of the mental imagery fixed in the Ukrainian public consciousness. Analysing the graphic artists’ responses and their use Christian imagery demonstrated how the war stimulated the creation of a new mythology, a new pantheon of heroes, designed to motivate, resist and , ultimately, lead to victory. The images of Christian saints, whose iconography was reinterpreted in several graphic works, gained particular importance for forming this new mythology.

Effects of lifestyle intervention on IGF-1, IGFBP-3, and insulin resistance in children with obesity with or without metabolic-associated fatty liver disease.

Obesity is a strong predictor for metabolic associated fatty liver disease (MAFLD), which has been associated with decreased insulin like growth factor 1 (IGF-1). In obesity, weight loss increases growth hormone secretion, but this is not unequivocally associated with increases in serum IGF-1 and IGF binding protein-3 (IGFBP-3). We studied the changes in the IGF axis in relation to weight loss and improvement in insulin resistance in children with or without MALFD after 10weeks of lifestyle intervention at a weight loss camp (WLC). We investigated 113 (66 females) Caucasian children with obesity, median age 12.4 (range 7.3-14.6) years, before and after 10weeks of lifestyle intervention at a WLC. We investigated children who was either MAFLD positive (n = 54) or negative (n = 59) before and after WLC. Children with MAFLD had lower baseline IGF-1 (249 ± 112 vs 278 ± 107µg/l, P = 0.048), whereas the IGF-1/IGFBP-3 molar ratio was similar to children without MAFLD (19.4 ± 6.6 vs. 21.8 ± 6.6%, P = 0.108). When all children were considered as one group, WLC decreased SDS-BMI and HOMA-IR (P < 0.001, both) and increased IGF-1 (264 ± 110 vs 285 ± 108µg/l, P < 0.001) and the IGF/IGFBP-3 molar ratio (20.7 ± 6.7 vs 22.4 ± 6.1%, P < 0.001). When categorized according to liver status, IGF-1 increased significantly in children with MAFLD (P = 0.008) and tended to increase in children without MAFLD (P = 0.052). Conclusions: Ten weeks of lifestyle intervention decreased insulin resistance and improved the IGF axis. We observed slight differences in the IGF axis in relation to MAFLD status. This suggests that the IGF axis is primarily influenced by insulin resistance rather than MAFLD status. What is New: •Weight loss decreases insulin resistance and subsequently increases the IGF axis in children with obesity. •Children with MAFLD had an aberration in the IGF axis compared to their MAFLD negative counter parts and the IGF axis was primarily influenced by the decreased BMI-SDS and insulin resistance, rather than MAFLD status. What is Known: • NAFLD has previously been associated with reduced serum IGF-1 concentrations. • Data on the impact of MAFLD and aberrations in the growth hormone and IGF axis and the effects of lifestyle interventions in children are limited.

Behavior and Damage Characterization of Impulsively Loaded Cross-Laminated Timber Panels

This research bridges the gap between the quasi-static and high-strain-rate loading regimes in cross-laminated timber (CLT) by investigating two areas that have remained unstudied or elusive, i.e., rolling shear failure of CLT under impulsive, blast-like loading and intermediate strain rates in CLT. To study the conditions that would promote shear modes of failure, a novel, highly adaptable center-point testing system and methodology were developed that permitted the application of impulsive loading to undamaged CLT panels in a highly controlled and repeatable manner. The loading condition and low span-to-depth ratio (6.40 ≤ L:h ≤ 6.55) CLT were selected to encourage the development of shear modes of failure. Changes to the rotational rigidity at the boundary conditions allowed for the empirical simulation of realistic boundary conditions. Digital Image Correlation (DIC) and load cell data were used to identify failure modes following loss in resistance in the specimens. Overall, the experiment was successful in consistently eliciting shear modes of failure and providing damage characterization in impulsively loaded CLT. Shear modes of failure resulted in the dramatic loss of resistance in all specimens tested. Strain-rate enhancement in the dynamic apparent flexural stiffness of CLT of 1.3 to 7.2 times was observed. Lower levels of damage were observed in specimens with higher levels of boundary-condition rotational rigidity.